U.S. patent application number 17/446283 was filed with the patent office on 2022-03-03 for resource reservation for nr-u sl.
The applicant listed for this patent is QUALCOMM Incorporated. Invention is credited to Chih-Hao Liu, Jing Sun, Yisheng Xue, Xiaoxia Zhang.
Application Number | 20220070925 17/446283 |
Document ID | / |
Family ID | 1000005930991 |
Filed Date | 2022-03-03 |
United States Patent
Application |
20220070925 |
Kind Code |
A1 |
Liu; Chih-Hao ; et
al. |
March 3, 2022 |
RESOURCE RESERVATION FOR NR-U SL
Abstract
In one aspect, a method of wireless communication includes
transmitting, by a user equipment (UE), a first transmission in a
first Channel Occupancy Time (COT) for a NR-U sidelink channel. The
method also includes reserving, by the UE, a resource in a
non-shared portion of a second COT and performing, by the UE, a
Listen-Before-Talk (LBT) Category (CAT) 4 operation at a start of
the second COT, wherein the second COT is associated with the UE.
The method includes performing, by the UE, a continuous
transmission operation in the second COT based on successfully
performing the LBT CAT 4 operation. The method further includes
transmitting, by the UE, a second transmission in the reserved
resource of the non-shared portion of the second COT based on
successfully performing a second LBT CAT 1 or 2 operation. Other
aspects and features are also claimed and described.
Inventors: |
Liu; Chih-Hao; (San Diego,
CA) ; Xue; Yisheng; (San Diego, CA) ; Zhang;
Xiaoxia; (San Diego, CA) ; Sun; Jing; (San
Diego, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
QUALCOMM Incorporated |
San Diego |
CA |
US |
|
|
Family ID: |
1000005930991 |
Appl. No.: |
17/446283 |
Filed: |
August 27, 2021 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
63071696 |
Aug 28, 2020 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04B 17/318 20150115;
H04W 74/0808 20130101; H04W 72/10 20130101 |
International
Class: |
H04W 74/08 20060101
H04W074/08; H04W 72/10 20060101 H04W072/10; H04B 17/318 20060101
H04B017/318 |
Claims
1. A method of wireless communication comprising: transmitting, by
a user equipment (UE), a first transmission in a first Channel
Occupancy Time (COT) for a NR-U sidelink channel; performing, by
the UE, a Listen-Before-Talk (LBT) Category (CAT) 4 operation at a
start of a second COT, wherein the second COT is associated with
the UE; and performing, by the UE, a continuous transmission
operation in the second COT based on successfully performing the
LBT CAT 4 operation; and transmitting, by the UE, a second
transmission in a reserved resource of a non-shared portion of the
second COT based on successfully performing a second LBT CAT 1 or 2
operation.
2. The method of claim 1, wherein the second COT includes the
non-shared portion and a shared portion, wherein the shared portion
occurs after the non-shared portion, and wherein the non-shared
portion of the second COT is reserved by the UE.
3. The method of claim 1, further comprising: reserving, by the UE,
a resource in the non-shared portion of the second COT to claim the
reserved resource, wherein the second transmission corresponds to a
retransmission of the first transmission or a new transmissions of
a new transmission block (TB).
4. The method of claim 3, wherein reserving the resource includes:
determining, by the UE, available resources of a resource selection
window (RSW) which occurs before a next reserved resource (RR) for
the UE; selecting, by the UE, a first set of available resources
from the available resources based on an earliest time; and
selecting, by the UE, a particular resource of the first set of
available resources based on a highest priority subchannel for the
second transmission.
5. The method of claim 4, wherein determining the available
resources includes: determining, by the UE, a reference signal
received power (RSRP) for each resource of the RSW; and comparing,
by the UE, each RSRP for each resource to a RSRP threshold, wherein
the available resources correspond to resources where the RSRP is
less than or equal to the RSRP threshold.
6. The method of claim 5, wherein determining the available
resources further includes: determining, by the UE, one or more
unavailable resources of the RSW based on the RSRP being greater
than the RSRP threshold.
7. The method of claim 3, wherein reserving the resource includes:
determining, by the UE, available resources of a resource selection
window (RSW) which occurs before a next reserved resource (RR) for
the UE; assigning, by the UE, a priority to each available resource
based on an earliest time and based on a highest priority
subchannel for the RSW; and selecting, by the UE, a particular
resource based on an assigned priority, wherein earlier times and
particular subchannels are associated with higher priority.
8. The method of claim 3, wherein reserving the resource includes:
determining, by the UE, available resources of a resource selection
window (RSW) which occurs before a next reserved resource (RR) for
the UE; assigning, by the UE, a priority to each available resource
based on an earliest time and based on a highest priority
subchannel for the RSW; and selecting, by the UE, a particular
available resource based on an earliest time with time-division
multiplexing on a first priority subchannel available.
9. The method of claim 3, wherein reserving the resource includes:
determining, by the UE, available resources of a resource selection
window (RSW) which occur before a next reserved resource (RR) for
the UE; assigning, by the UE, a priority to each available resource
of a first priority subchannel based on earliest time; and
assigning, by the UE, a priority to available resources of a second
priority subchannel based on earliest time.
10. An apparatus configured for wireless communication, comprising:
at least one processor; and a memory coupled to the at least one
processor, wherein the at least one processor is configured to:
transmit a first transmission in a first Channel Occupancy Time
(COT) for a NR-U sidelink channel; perform a Listen-Before-Talk
(LBT) Category (CAT) 4 operation at a start of a second COT,
wherein the second COT is associated with the apparatus; perform a
continuous transmission operation in the second COT based on
successfully performing the LBT CAT 4 operation; and transmit a
second transmission in a reserved resource of a non-shared portion
of the second COT based on successfully performing a second LBT CAT
1 or 2 operation.
11. The apparatus of claim 10, wherein performing the continuous
transmission operation includes continuously transmitting from
after the LBT CAT 4 operation to at least a start of a shared
portion of the second COT based on successfully performing the LBT
CAT 4 operation, and wherein a second apparatus transmits before a
second reserved resource (RR) of the apparatus in the shared
portion of the second COT.
12. The apparatus of claim 10, wherein the processor is further
configured to: reserve a second resource in a shared portion of the
second COT; and wherein the continuous transmission operation
includes to continuously transmit for one or more second slots of
the second COT before the second reserved resource based on
successfully performing the LBT CAT 4 operation; and transmit a
third transmission in the second reserved resource.
13. The apparatus of claim 10, wherein the processor is further
configured to: reduce a shared portion of the second COT; and
increase the non-shared portion of the second COT to generate an
enlarged non-shared portion of the second COT, wherein a reserved
resource (RR) of the apparatus is scheduled in the enlarged
non-shared portion of the second COT.
14. The apparatus of claim 10, wherein the processor is further
configured to: reserve a particular subchannel of the second COT,
and wherein to perform the continuous transmission operation
includes to transmit a continuous transmission in the particular
subchannel of the second COT.
15. The apparatus of claim 14, wherein the reserved particular
subchannel is excluded from other UE resource selection or
reservation in the non-shared portion, a shared portion, or both,
of the second COT, wherein the apparatus prioritizes the reserved
particular subchannel for resource reservation, and wherein the
apparatus prioritizes earlier time slots within the reserved
particular subchannel.
16. The apparatus of claim 14, wherein to perform the continuous
transmission operation includes to continuously transmit packets
before a reserved resource (RR) in a shared portion of the second
COT.
17. The apparatus of claim 14, wherein to perform the continuous
transmission operation includes continuously transmitting in a
shared portion of the second COT while leaving a LBT gap for each
slot in the reserved particular subchannel for other apparatuses to
clear before transmitting in other subchannels.
18. The apparatus of claim 14, wherein to perform the continuous
transmission operation includes continuously transmitting in a
shared portion of the second COT without leaving one or more LBT
gaps.
19. An apparatus configured for wireless communication, comprising:
means for transmitting a first transmission in a first Channel
Occupancy Time (COT) for a NR-U sidelink channel; means for
performing a Listen-Before-Talk (LBT) Category (CAT) 4 operation at
a start of a second COT, wherein the second COT is associated with
the UE; means for performing a continuous transmission operation in
the second COT based on successfully performing the LBT CAT 4
operation; and, means for transmitting a second transmission in a
reserved resource of a non-shared portion of the second COT based
on successfully performing a second LBT CAT 1 or 2 operation.
20. The apparatus of claim 19, further comprising: means for
determining, prior to transmitting the second transmission, that a
future reserved resource (RR) of the apparatus is scheduled in a
shared portion of the second COT, which is assigned to the
apparatus; and means for moving the future RR of the apparatus to
the non-shared portion of the second COT, the future RR
corresponding to the second transmission.
21. The apparatus of claim 20, further comprising: means for
determining that a second future RR of the apparatus is scheduled
in the shared portion of the second COT; and means for moving the
second future RR of the apparatus to the non-shared portion of the
second COT.
22. The apparatus of claim 20, wherein the second LBT CAT 1 or 2
operation is performed before the future RR based on determining a
second transmission block (TB) is ready to be transmitted in a
second Hybrid automatic repeat request (HARQ) process different
from a first HARQ process of the first COT, and further comprising:
means for transmitting a third transmission for the second TB at a
first time in a first subchannel of the non-shared portion of the
second COT, wherein the future RR is scheduled at the first time in
a second subchannel of the non-shared portion of the second COT,
wherein the second future RR is scheduled at a second time in the
first subchannel of the non-shared portion of the second COT, and
wherein the third transmission is frequency division multiplexed
with the second transmission of the future RR.
23. The apparatus of claim 19, further comprising: means for
determining whether a reserved resource (RR) for the second
transmission is within the second COT or outside of the second COT;
and means for determining a reference signal received power (RSRP)
threshold for resource selection based on determining whether the
RR is within the second COT or outside of the second COT.
24. The apparatus of claim 23, wherein the RR is outside of the
second COT, and wherein the means for determining the RSRP
threshold for resource selection includes: means for reducing a
value of the RSRP threshold by a priority offset value; or means
for selecting a second RSRP threshold that is less than a first
RSRP threshold for RRs inside of the second COT.
25. A non-transitory, computer-readable medium storing instructions
that, when executed by a processor, cause the processor to perform
operations comprising: transmitting, by a user equipment (UE), a
first transmission in a first Channel Occupancy Time (COT) for a
NR-U sidelink channel; performing, by the UE, a Listen-Before-Talk
(LBT) Category (CAT) 4 operation at a start of a second COT,
wherein the second COT is associated with the UE; performing, by
the UE, a continuous transmission operation in the second COT based
on successfully performing the LBT CAT 4 operation; and
transmitting a second transmission in a reserved resource of a
non-shared portion of the second COT based on successfully
performing a second LBT CAT 1 or 2 operation.
26. The non-transitory, computer-readable medium of claim 25,
wherein the instructions further cause the processor perform
operations comprising: receiving, by the UE, a sidelink channel
information (SCI) transmission from another UE requesting to
schedule a reserved resource (RR) for the other UE in a non-shared
portion of a second COT allocated to the UE, wherein the SCI
transmission indicates offset information and subchannel
information for the RR; determining, by the UE, to block the
request; determining, by the UE, to schedule the RR for the other
UE in a shared portion of the second COT; and transmitting, by the
UE, a message to the other UE indicating that the RR for the other
UE has been moved to the shared portion of the second COT.
27. The non-transitory, computer-readable medium of claim 26,
wherein the message is a SCI-1, wherein the SCI-1 indicates a slot
offset and subchannel for the RR for the other UE, and wherein the
SCI-1 is associated with a single Hybrid automatic repeat request
(HARQ) ID.
28. The non-transitory, computer-readable medium of claim 27,
wherein the instructions further cause the processor perform
operations comprising: transmitting, by the UE, a plurality of
SCI-1 transmissions, including the SCI-1, wherein multiple sets of
RRs are associated with multiple HARQ IDs.
29. The non-transitory, computer-readable medium of claim 25,
wherein the instructions further cause the processor perform
operations comprising: determining, by the UE, that a second
reserved resource (RR) for the UE has blocked a RR for a second UE
in a non-shared portion of the second COT; determining, by the UE,
to schedule the RR for the second UE to a shared portion of the
second COT based on determining that the second RR for the UE has
blocked the RR for the second UE in the non-shared portion of the
second COT; and transmitting, by the UE, a sidelink channel
information (SCI) transmission to the second UE to schedule the RR
for the second UE, wherein the second UE uses single step resource
selection.
30. The non-transitory, computer-readable medium of claim 29,
wherein the SCI transmission corresponds to a SCI-2 transmission,
wherein the SCI-2 transmission indicates information for the
relocation of the RR for the second UE, and wherein the SCI-2
transmission includes source ID information which indicates a
transmitting UE ID for the RR, destination ID information which
indicates a receiving UE ID for the RR, Hybrid automatic repeat
request (HARQ) ID information which indicates the RR associated
with specific HARQ ID has been relocated, or a combination thereof.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Patent Application No. 63/071,696, entitled, "RESOURCE RESERVATION
FOR NR-U SL," filed on Aug. 28, 2020, which is expressly
incorporated by reference herein in its entirety.
FIELD
[0002] Aspects of the present disclosure relate generally to
wireless communication systems, and more particularly, to resource
reservation for sidelink channel communications.
BACKGROUND
[0003] Wireless communication networks are widely deployed to
provide various communication services such as voice, video, packet
data, messaging, broadcast, and the like. These wireless networks
may be multiple-access networks capable of supporting multiple
users by sharing the available network resources. Such networks,
which are usually multiple access networks, support communications
for multiple users by sharing the available network resources. One
example of such a network is the Universal Terrestrial Radio Access
Network (UTRAN). The UTRAN is the radio access network (RAN)
defined as a part of the Universal Mobile Telecommunications System
(UMTS), a third generation (3G) mobile phone technology supported
by the 3rd Generation Partnership Project (3GPP). Examples of
multiple-access network formats include Code Division Multiple
Access (CDMA) networks, Time Division Multiple Access (TDMA)
networks, Frequency Division Multiple Access (FDMA) networks,
Orthogonal FDMA (OFDMA) networks, and Single-Carrier FDMA (SC-FDMA)
networks.
[0004] A wireless communication network may include a number of
base stations or node Bs that can support communication for a
number of user equipments (UEs). A UE may communicate with a base
station via downlink and uplink. The downlink (or forward link)
refers to the communication link from the base station to the UE,
and the uplink (or reverse link) refers to the communication link
from the UE to the base station.
[0005] A base station may transmit data and control information on
the downlink to a UE and/or may receive data and control
information on the uplink from the UE. On the downlink, a
transmission from the base station may encounter interference due
to transmissions from neighbor base stations or from other wireless
radio frequency (RF) transmitters. On the uplink, a transmission
from the UE may encounter interference from uplink transmissions of
other UEs communicating with the neighbor base stations or from
other wireless RF transmitters. This interference may degrade
performance on both the downlink and uplink.
[0006] As the demand for mobile broadband access continues to
increase, the possibilities of interference and congested networks
grows with more UEs accessing the long-range wireless communication
networks and more short-range wireless systems being deployed in
communities. Research and development continue to advance wireless
technologies not only to meet the growing demand for mobile
broadband access, but to advance and enhance the user experience
with mobile communications.
SUMMARY
[0007] In one aspect of the disclosure, a method of wireless
communication includes transmitting, by a user equipment (UE), a
first transmission in a first Channel Occupancy Time (COT) for a
NR-U sidelink channel; reserving, by the UE, a resource in a
non-shared portion of a second COT; performing, by the UE, a
Listen-Before-Talk (LBT) Category (CAT) 4 operation at a start of
the second COT, wherein the second COT is associated with the UE;
performing, by the UE, a continuous transmission operation in the
second COT based on successfully performing the LBT CAT 4
operation; and transmitting, by the UE, a second transmission in
the reserved resource of the non-shared portion of the second COT
based on successfully performing a second LBT CAT 1 or 2
operation.
[0008] In an additional aspect of the disclosure, an apparatus
configured for wireless communication is disclosed. The apparatus
includes means for transmitting, by a user equipment (UE), a first
transmission in a first Channel Occupancy Time (COT) for a NR-U
sidelink channel; means for reserving, by the UE, a resource in a
non-shared portion of a second COT; means for performing, by the
UE, a Listen-Before-Talk (LBT) Category (CAT) 4 operation at a
start of the second COT; means for performing, by the UE, a
continuous transmission operation in the second COT based on
successfully performing the LBT CAT 4 operation, wherein the second
COT is associated with the UE; and means for transmitting, by the
UE, a second transmission in the reserved resource of the
non-shared portion of the second COT based on successfully
performing a second LBT CAT 1 or 2 operation.
[0009] In an additional aspect of the disclosure, a non-transitory
computer-readable medium having program code recorded thereon. The
program code further includes code to transmit, by a user equipment
(UE), a first transmission in a first Channel Occupancy Time (COT)
for a NR-U sidelink channel; reserve, by the UE, a resource in a
non-shared portion of a second COT; perform, by the UE, a
Listen-Before-Talk (LBT) Category (CAT) 4 operation at a start of
the second COT; perform, by the UE, a continuous transmission
operation in the second COT based on successfully performing the
LBT CAT 4 operation, wherein the second COT is associated with the
UE; and transmit, by the UE, a second transmission in the reserved
resource of the non-shared portion of the second COT based on
successfully performing a second LBT CAT 1 or 2 operation.
[0010] In an additional aspect of the disclosure, an apparatus
configured for wireless communication is disclosed. The apparatus
includes at least one processor, and a memory coupled to the
processor. The processor is configured to transmit, by a user
equipment (UE), a first transmission in a first Channel Occupancy
Time (COT) for a NR-U sidelink channel; reserve, by the UE, a
resource in a non-shared portion of a second COT; perform, by the
UE, a Listen-Before-Talk (LBT) Category (CAT) 4 operation at a
start of the second COT; performing, by the UE, a continuous
transmission operation in the second COT based on successfully
performing the LBT CAT 4 operation, wherein the second COT is
associated with the UE; and transmit, by the UE, a second
transmission in the reserved resource of the non-shared portion of
the second COT based on successfully performing a second LBT CAT 1
or 2 operation.
[0011] The foregoing has outlined rather broadly the features and
technical advantages of examples according to the disclosure in
order that the detailed description that follows may be better
understood. Additional features and advantages will be described
hereinafter. The conception and specific examples disclosed may be
readily utilized as a basis for modifying or designing other
structures for carrying out the same purposes of the present
disclosure. Such equivalent constructions do not depart from the
scope of the appended claims. Characteristics of the concepts
disclosed herein, both their organization and method of operation,
together with associated advantages will be better understood from
the following description when considered in connection with the
accompanying figures. Each of the figures is provided for the
purpose of illustration and description, and not as a definition of
the limits of the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] A further understanding of the nature and advantages of the
present disclosure may be realized by reference to the following
drawings. In the appended figures, similar components or features
may have the same reference label. Further, various components of
the same type may be distinguished by following the reference label
by a dash and a second label that distinguishes among the similar
components. If just the first reference label is used in the
specification, the description is applicable to any one of the
similar components having the same first reference label
irrespective of the second reference label.
[0013] FIG. 1 is a block diagram illustrating details of a wireless
communication system.
[0014] FIG. 2 is a block diagram illustrating a design of a base
station and a UE configured according to one aspect of the present
disclosure.
[0015] FIG. 3 is a timing diagram illustrating coordinated resource
partitioning.
[0016] FIG. 4 is a block diagram illustrating an example of a
wireless communications system (with a UE and base station) with
enhanced resource reservation operations.
[0017] FIG. 5 is a diagram illustrating an example of continuous
transmission operations according to some embodiments of the
present disclosure.
[0018] FIG. 6 is a diagram illustrating an example of resource
selection according to some embodiments of the present
disclosure.
[0019] FIG. 7 is a diagram illustrating another example of
continuous transmission operations according to some embodiments of
the present disclosure.
[0020] FIG. 8 is a diagram illustrating an example of resource
relocation according to some embodiments of the present
disclosure.
[0021] FIG. 9 is a diagram illustrating an example of in and out of
COT priority for resource selection according to some embodiments
of the present disclosure.
[0022] FIG. 10 is a diagram illustrating another example of
resource relocation according to some embodiments of the present
disclosure.
[0023] FIG. 11 is a flow diagram illustrating example blocks
executed by a UE configured according to an aspect of the present
disclosure.
[0024] FIG. 12 is a flow diagram illustrating example blocks
executed by a UE configured according to another aspect of the
present disclosure.
[0025] FIG. 13 is a block diagram conceptually illustrating a
design of a UE configured to perform precoding information update
operations according to some embodiments of the present
disclosure.
DETAILED DESCRIPTION
[0026] The detailed description set forth below, in connection with
the appended drawings, is intended as a description of various
configurations and is not intended to limit the scope of the
disclosure. Rather, the detailed description includes specific
details for the purpose of providing a thorough understanding of
the inventive subject matter. It will be apparent to those skilled
in the art that these specific details are not required in every
case and that, in some instances, well-known structures and
components are shown in block diagram form for clarity of
presentation.
[0027] This disclosure relates generally to providing or
participating in authorized shared access between two or more
wireless communications systems, also referred to as wireless
communications networks. In various embodiments, the techniques and
apparatus may be used for wireless communication networks such as
code division multiple access (CDMA) networks, time division
multiple access (TDMA) networks, frequency division multiple access
(FDMA) networks, orthogonal FDMA (OFDMA) networks, single-carrier
FDMA (SC-FDMA) networks, LTE networks, GSM networks, 5.sup.th
Generation (5G) or new radio (NR) networks, as well as other
communications networks. As described herein, the terms "networks"
and "systems" may be used interchangeably.
[0028] An OFDMA network may implement a radio technology such as
evolved UTRA (E-UTRA), IEEE 802.11, IEEE 802.16, IEEE 802.20,
flash-OFDM and the like. UTRA, E-UTRA, and Global System for Mobile
Communications (GSM) are part of universal mobile telecommunication
system (UMTS). In particular, long term evolution (LTE) is a
release of UMTS that uses E-UTRA. UTRA, E-UTRA, GSM, UMTS and LTE
are described in documents provided from an organization named "3rd
Generation Partnership Project" (3GPP), and cdma2000 is described
in documents from an organization named "3rd Generation Partnership
Project 2" (3GPP2). These various radio technologies and standards
are known or are being developed. For example, the 3rd Generation
Partnership Project (3GPP) is a collaboration between groups of
telecommunications associations that aims to define a globally
applicable third generation (3G) mobile phone specification. 3GPP
long term evolution (LTE) is a 3GPP project which was aimed at
improving the universal mobile telecommunications system (UMTS)
mobile phone standard. The 3GPP may define specifications for the
next generation of mobile networks, mobile systems, and mobile
devices. The present disclosure is concerned with the evolution of
wireless technologies from LTE, 4G, 5G, NR, and beyond with shared
access to wireless spectrum between networks using a collection of
new and different radio access technologies or radio air
interfaces.
[0029] In particular, 5G networks contemplate diverse deployments,
diverse spectrum, and diverse services and devices that may be
implemented using an OFDM-based unified, air interface. In order to
achieve these goals, further enhancements to LTE and LTE-A are
considered in addition to development of the new radio technology
for 5G NR networks. The 5G NR will be capable of scaling to provide
coverage (1) to a massive Internet of things (IoTs) with an
ultra-high density (e.g., .about.1 M nodes/km.sup.2), ultra-low
complexity (e.g., .about.10 s of bits/sec), ultra-low energy (e.g.,
.about.10+ years of battery life), and deep coverage with the
capability to reach challenging locations; (2) including
mission-critical control with strong security to safeguard
sensitive personal, financial, or classified information,
ultra-high reliability (e.g., .about.99.9999% reliability),
ultra-low latency (e.g., .about.1 ms), and users with wide ranges
of mobility or lack thereof; and (3) with enhanced mobile broadband
including extreme high capacity (e.g., .about.10 Tbps/km.sup.2),
extreme data rates (e.g., multi-Gbps rate, 100+ Mbps user
experienced rates), and deep awareness with advanced discovery and
optimizations.
[0030] The 5G NR may be implemented to use optimized OFDM-based
waveforms with scalable numerology and transmission time interval
(TTI); having a common, flexible framework to efficiently multiplex
services and features with a dynamic, low-latency time division
duplex (TDD)/frequency division duplex (FDD) design; and with
advanced wireless technologies, such as massive multiple input,
multiple output (MIMO), robust millimeter wave (mmWave)
transmissions, advanced channel coding, and device-centric
mobility. Scalability of the numerology in 5G NR, with scaling of
subcarrier spacing, may efficiently address operating diverse
services across diverse spectrum and diverse deployments. For
example, in various outdoor and macro coverage deployments of less
than 3GHz FDD/TDD implementations, subcarrier spacing may occur
with 15 kHz, for example over 1, 5, 10, 20 MHz, and the like
bandwidth. For other various outdoor and small cell coverage
deployments of TDD greater than 3 GHz, subcarrier spacing may occur
with 30 kHz over 80/100 MHz bandwidth. For other various indoor
wideband implementations, using a TDD over the unlicensed portion
of the 5 GHz band, the subcarrier spacing may occur with 60 kHz
over a 160 MHz bandwidth. Finally, for various deployments
transmitting with mmWave components at a TDD of 28 GHz, subcarrier
spacing may occur with 120 kHz over a 500 MHz bandwidth.
[0031] The scalable numerology of the 5G NR facilitates scalable
TTI for diverse latency and quality of service (QoS) requirements.
For example, shorter TTI may be used for low latency and high
reliability, while longer TTI may be used for higher spectral
efficiency. The efficient multiplexing of long and short TTIs to
allow transmissions to start on symbol boundaries. 5G NR also
contemplates a self-contained integrated subframe design with
uplink/downlink scheduling information, data, and acknowledgement
in the same subframe. The self-contained integrated subframe
supports communications in unlicensed or contention-based shared
spectrum, adaptive uplink/downlink that may be flexibly configured
on a per-cell basis to dynamically switch between uplink and
downlink to meet the current traffic needs.
[0032] Various other aspects and features of the disclosure are
further described below. It should be apparent that the teachings
herein may be embodied in a wide variety of forms and that any
specific structure, function, or both being disclosed herein is
merely representative and not limiting. Based on the teachings
herein one of an ordinary level of skill in the art should
appreciate that an aspect disclosed herein may be implemented
independently of any other aspects and that two or more of these
aspects may be combined in various ways. For example, an apparatus
may be implemented or a method may be practiced using any number of
the aspects set forth herein. In addition, such an apparatus may be
implemented or such a method may be practiced using other
structure, functionality, or structure and functionality in
addition to or other than one or more of the aspects set forth
herein. For example, a method may be implemented as part of a
system, device, apparatus, and/or as instructions stored on a
computer readable medium for execution on a processor or computer.
Furthermore, an aspect may comprise at least one element of a
claim.
[0033] FIG. 1 is a block diagram illustrating 5G network 100
including various base stations and UEs configured according to
aspects of the present disclosure. The 5G network 100 includes a
number of base stations 105 and other network entities. A base
station may be a station that communicates with the UEs and may
also be referred to as an evolved node B (eNB), a next generation
eNB (gNB), an access point, and the like. Each base station 105 may
provide communication coverage for a particular geographic area. In
3GPP, the term "cell" can refer to this particular geographic
coverage area of a base station and/or a base station subsystem
serving the coverage area, depending on the context in which the
term is used.
[0034] A base station may provide communication coverage for a
macro cell or a small cell, such as a pico cell or a femto cell,
and/or other types of cell. A macro cell generally covers a
relatively large geographic area (e.g., several kilometers in
radius) and may allow unrestricted access by UEs with service
subscriptions with the network provider. A small cell, such as a
pico cell, would generally cover a relatively smaller geographic
area and may allow unrestricted access by UEs with service
subscriptions with the network provider. A small cell, such as a
femto cell, would also generally cover a relatively small
geographic area (e.g., a home) and, in addition to unrestricted
access, may also provide restricted access by UEs having an
association with the femto cell (e.g., UEs in a closed subscriber
group (CSG), UEs for users in the home, and the like). A base
station for a macro cell may be referred to as a macro base
station. A base station for a small cell may be referred to as a
small cell base station, a pico base station, a femto base station
or a home base station. In the example shown in FIG. 1, the base
stations 105d and 105e are regular macro base stations, while base
stations 105a-105c are macro base stations enabled with one of 3
dimension (3D), full dimension (FD), or massive MIMO. Base stations
105a-105c take advantage of their higher dimension MIMO
capabilities to exploit 3D beamforming in both elevation and
azimuth beamforming to increase coverage and capacity. Base station
105f is a small cell base station which may be a home node or
portable access point. A base station may support one or multiple
(e.g., two, three, four, and the like) cells.
[0035] The 5G network 100 may support synchronous or asynchronous
operation. For synchronous operation, the base stations may have
similar frame timing, and transmissions from different base
stations may be approximately aligned in time. For asynchronous
operation, the base stations may have different frame timing, and
transmissions from different base stations may not be aligned in
time.
[0036] The UEs 115 are dispersed throughout the wireless network
100, and each UE may be stationary or mobile. A UE may also be
referred to as a terminal, a mobile station, a subscriber unit, a
station, or the like. A UE may be a cellular phone, a personal
digital assistant (PDA), a wireless modem, a wireless communication
device, a handheld device, a tablet computer, a laptop computer, a
cordless phone, a wireless local loop (WLL) station, or the like.
In one aspect, a UE may be a device that includes a Universal
Integrated Circuit Card (UICC). In another aspect, a UE may be a
device that does not include a UICC. In some aspects, UEs that do
not include UICCs may also be referred to as internet of everything
(IoE) or internet of things (IoT) devices. UEs 115a-115d are
examples of mobile smart phone-type devices accessing 5G network
100 A UE may also be a machine specifically configured for
connected communication, including machine type communication
(MTC), enhanced MTC (eMTC), narrowband IoT (NB-IoT) and the like.
UEs 115a-115k are examples of various machines configured for
communication that access 5G network 100. A UE may be able to
communicate with any type of the base stations, whether macro base
station, small cell, or the like. In FIG. 1, a lightning bolt
(e.g., communication links) indicates wireless transmissions
between a UE and a serving base station, which is a base station
designated to serve the UE on the downlink and/or uplink, or
desired transmission between base stations, and backhaul
transmissions between base stations.
[0037] In operation at 5G network 100, base stations 105a-105c
serve UEs 115a and 115b using 3D beamforming and coordinated
spatial techniques, such as coordinated multipoint (CoMP) or
multi-connectivity. Macro base station 105d performs backhaul
communications with base stations 105a-105c, as well as small cell,
base station 105f. Macro base station 105d also transmits multicast
services which are subscribed to and received by UEs 115c and 115d.
Such multicast services may include mobile television or stream
video, or may include other services for providing community
information, such as weather emergencies or alerts, such as Amber
alerts or gray alerts.
[0038] 5G network 100 also support mission critical communications
with ultra-reliable and redundant links for mission critical
devices, such UE 115e, which is a drone. Redundant communication
links with UE 115e include from macro base stations 105d and 105e,
as well as small cell base station 105f. Other machine type
devices, such as UE 115f (thermometer), UE 115g (smart meter), and
UE 115h (wearable device) may communicate through 5G network 100
either directly with base stations, such as small cell base station
105f, and macro base station 105e, or in multi-hop configurations
by communicating with another user device which relays its
information to the network, such as UE 115f communicating
temperature measurement information to the smart meter, UE 115g,
which is then reported to the network through small cell base
station 105f. 5G network 100 may also provide additional network
efficiency through dynamic, low-latency TDD/FDD communications,
such as in a vehicle-to-vehicle (V2V) mesh network between UEs
115i-115k communicating with macro base station 105e.
[0039] FIG. 2 shows a block diagram of a design of a base station
105 and a UE 115, which may be one of the base station and one of
the UEs in FIG. 1. At the base station 105, a transmit processor
220 may receive data from a data source 212 and control information
from a controller/processor 240. The control information may be for
the PBCH, PCFICH, PHICH, PDCCH, EPDCCH, MPDCCH etc. The data may be
for the PDSCH, etc. The transmit processor 220 may process (e.g.,
encode and symbol map) the data and control information to obtain
data symbols and control symbols, respectively. The transmit
processor 220 may also generate reference symbols, e.g., for the
PSS, SSS, and cell-specific reference signal. A transmit (TX)
multiple-input multiple-output (MIMO) processor 230 may perform
spatial processing (e.g., precoding) on the data symbols, the
control symbols, and/or the reference symbols, if applicable, and
may provide output symbol streams to the modulators (MODs) 232a
through 232t. Each modulator 232 may process a respective output
symbol stream (e.g., for OFDM, etc.) to obtain an output sample
stream. Each modulator 232 may further process (e.g., convert to
analog, amplify, filter, and upconvert) the output sample stream to
obtain a downlink signal. Downlink signals from modulators 232a
through 232t may be transmitted via the antennas 234a through 234t,
respectively.
[0040] At the UE 115, the antennas 252a through 252r may receive
the downlink signals from the base station 105 and may provide
received signals to the demodulators (DEMODs) 254a through 254r,
respectively. Each demodulator 254 may condition (e.g., filter,
amplify, downconvert, and digitize) a respective received signal to
obtain input samples. Each demodulator 254 may further process the
input samples (e.g., for OFDM, etc.) to obtain received symbols. A
MIMO detector 256 may obtain received symbols from all the
demodulators 254a through 254r, perform MIMO detection on the
received symbols if applicable, and provide detected symbols. A
receive processor 258 may process (e.g., demodulate, deinterleave,
and decode) the detected symbols, provide decoded data for the UE
115 to a data sink 260, and provide decoded control information to
a controller/processor 280.
[0041] On the uplink, at the UE 115, a transmit processor 264 may
receive and process data (e.g., for the PUSCH) from a data source
262 and control information (e.g., for the PUCCH) from the
controller/processor 280. The transmit processor 264 may also
generate reference symbols for a reference signal. The symbols from
the transmit processor 264 may be precoded by a TX MIMO processor
266 if applicable, further processed by the modulators 254a through
254r (e.g., for SC-FDM, etc.), and transmitted to the base station
105. At the base station 105, the uplink signals from the UE 115
may be received by the antennas 234, processed by the demodulators
232, detected by a MIMO detector 236 if applicable, and further
processed by a receive processor 238 to obtain decoded data and
control information sent by the UE 115. The processor 238 may
provide the decoded data to a data sink 239 and the decoded control
information to the controller/processor 240.
[0042] The controllers/processors 240 and 280 may direct the
operation at the base station 105 and the UE 115, respectively. The
controller/processor 240 and/or other processors and modules at the
base station 105 may perform or direct the execution of various
processes for the techniques described herein. The
controllers/processor 280 and/or other processors and modules at
the UE 115 may also perform or direct the execution of the
functional blocks illustrated in FIGS. 11 and 12, and/or other
processes for the techniques described herein. The memories 242 and
282 may store data and program codes for the base station 105 and
the UE 115, respectively. A scheduler 244 may schedule UEs for data
transmission on the downlink and/or uplink.
[0043] Wireless communications systems operated by different
network operating entities (e.g., network operators) may share
spectrum. In some instances, a network operating entity may be
configured to use an entirety of a designated shared spectrum for
at least a period of time before another network operating entity
uses the entirety of the designated shared spectrum for a different
period of time. Thus, in order to allow network operating entities
use of the full designated shared spectrum, and in order to
mitigate interfering communications between the different network
operating entities, certain resources (e.g., time) may be
partitioned and allocated to the different network operating
entities for certain types of communication.
[0044] For example, a network operating entity may be allocated
certain time resources reserved for exclusive communication by the
network operating entity using the entirety of the shared spectrum.
The network operating entity may also be allocated other time
resources where the entity is given priority over other network
operating entities to communicate using the shared spectrum. These
time resources, prioritized for use by the network operating
entity, may be utilized by other network operating entities on an
opportunistic basis if the prioritized network operating entity
does not utilize the resources. Additional time resources may be
allocated for any network operator to use on an opportunistic
basis.
[0045] Access to the shared spectrum and the arbitration of time
resources among different network operating entities may be
centrally controlled by a separate entity, autonomously determined
by a predefined arbitration scheme, or dynamically determined based
on interactions between wireless nodes of the network
operators.
[0046] In some cases, UE 115 and base station 105 of the 5G network
100 (in FIG. 1) may operate in a shared radio frequency spectrum
band, which may include licensed or unlicensed (e.g.,
contention-based) frequency spectrum. In an unlicensed frequency
portion of the shared radio frequency spectrum band, UEs 115 or
base stations 105 may traditionally perform a medium-sensing
procedure to contend for access to the frequency spectrum. For
example, UE 115 or base station 105 may perform a listen before
talk (LBT) procedure such as a clear channel assessment (CCA) prior
to communicating in order to determine whether the shared channel
is available. A CCA may include an energy detection procedure to
determine whether there are any other active transmissions. For
example, a device may infer that a change in a received signal
strength indicator (RSSI) of a power meter indicates that a channel
is occupied. Specifically, signal power that is concentrated in a
certain bandwidth and exceeds a predetermined noise floor may
indicate another wireless transmitter. A CCA also may include
detection of specific sequences that indicate use of the channel.
For example, another device may transmit a specific preamble prior
to transmitting a data sequence. In some cases, an LBT procedure
may include a wireless node adjusting its own backoff window based
on the amount of energy detected on a channel and/or the
acknowledge/negative-acknowledge (ACK/NACK) feedback for its own
transmitted packets as a proxy for collisions.
[0047] In general, four categories of LBT procedure have been
suggested for sensing a shared channel for signals that may
indicate the channel is already occupied. In a first category (CAT
1 LBT), no LBT or CCA is applied to detect occupancy of the shared
channel. A second category (CAT 2 LBT), which may also be referred
to as an abbreviated LBT, a single-shot LBT, or a 25-.mu.s LBT,
provides for the node to perform a CCA to detect energy above a
predetermined threshold or detect a message or preamble occupying
the shared channel. The CAT 2 LBT performs the CCA without using a
random back-off operation, which results in its abbreviated length,
relative to the next categories.
[0048] A third category (CAT 3 LBT) performs CCA to detect energy
or messages on a shared channel, but also uses a random back-off
and fixed contention window. Therefore, when the node initiates the
CAT 3 LBT, it performs a first CCA to detect occupancy of the
shared channel. If the shared channel is idle for the duration of
the first CCA, the node may proceed to transmit. However, if the
first CCA detects a signal occupying the shared channel, the node
selects a random back-off based on the fixed contention window size
and performs an extended CCA. If the shared channel is detected to
be idle during the extended CCA and the random number has been
decremented to 0, then the node may begin transmission on the
shared channel. Otherwise, the node decrements the random number
and performs another extended CCA. The node would continue
performing extended CCA until the random number reaches 0. If the
random number reaches 0 without any of the extended CCAs detecting
channel occupancy, the node may then transmit on the shared
channel. If at any of the extended CCA, the node detects channel
occupancy, the node may re-select a new random back-off based on
the fixed contention window size to begin the countdown again.
[0049] A fourth category (CAT 4 LBT), which may also be referred to
as a full LBT procedure, performs the CCA with energy or message
detection using a random back-off and variable contention window
size. The sequence of CCA detection proceeds similarly to the
process of the CAT 3 LBT, except that the contention window size is
variable for the CAT 4 LBT procedure.
[0050] Use of a medium-sensing procedure to contend for access to
an unlicensed shared spectrum may result in communication
inefficiencies. This may be particularly evident when multiple
network operating entities (e.g., network operators) are attempting
to access a shared resource. In the 5G network 100, base stations
105 and UEs 115 may be operated by the same or different network
operating entities. In some examples, an individual base station
105 or UE 115 may be operated by more than one network operating
entity. In other examples, each base station 105 and UE 115 may be
operated by a single network operating entity. Requiring each base
station 105 and UE 115 of different network operating entities to
contend for shared resources may result in increased signaling
overhead and communication latency.
[0051] FIG. 3 illustrates an example of a timing diagram 300 for
coordinated resource partitioning. The timing diagram 300 includes
a superframe 305, which may represent a fixed duration of time
(e.g., 20 ms). The superframe 305 may be repeated for a given
communication session and may be used by a wireless system such as
5G network 100 described with reference to FIG. 1. The superframe
305 may be divided into intervals such as an acquisition interval
(A-INT) 310 and an arbitration interval 315. As described in more
detail below, the A-INT 310 and arbitration interval 315 may be
subdivided into sub-intervals, designated for certain resource
types, and allocated to different network operating entities to
facilitate coordinated communications between the different network
operating entities. For example, the arbitration interval 315 may
be divided into a plurality of sub-intervals 320. Also, the
superframe 305 may be further divided into a plurality of subframes
325 with a fixed duration (e.g., 1 ms). While timing diagram 300
illustrates three different network operating entities (e.g.,
Operator A, Operator B, Operator C), the number of network
operating entities using the superframe 305 for coordinated
communications may be greater than or fewer than the number
illustrated in timing diagram 300.
[0052] The A-INT 310 may be a dedicated interval of the superframe
305 that is reserved for exclusive communications by the network
operating entities. In some examples, each network operating entity
may be allocated certain resources within the A-INT 310 for
exclusive communications. For example, resources 330-a may be
reserved for exclusive communications by Operator A, such as
through base station 105a, resources 330-b may be reserved for
exclusive communications by Operator B, such as through base
station 105b, and resources 330-c may be reserved for exclusive
communications by Operator C, such as through base station 105c.
Since the resources 330-a are reserved for exclusive communications
by Operator A, neither Operator B nor Operator C can communicate
during resources 330-a, even if Operator A chooses not to
communicate during those resources. That is, access to exclusive
resources is limited to the designated network operator. Similar
restrictions apply to resources 330-b for Operator B and resources
330-c for Operator C. The wireless nodes of Operator A (e.g., UEs
115 or base stations 105) may communicate any information desired
during their exclusive resources 330-a, such as control information
or data.
[0053] When communicating over an exclusive resource, a network
operating entity does not need to perform any medium sensing
procedures (e.g., listen-before-talk (LBT) or clear channel
assessment (CCA)) because the network operating entity knows that
the resources are reserved. Because only the designated network
operating entity may communicate over exclusive resources, there
may be a reduced likelihood of interfering communications as
compared to relying on medium sensing techniques alone (e.g., no
hidden node problem). In some examples, the A-INT 310 is used to
transmit control information, such as synchronization signals
(e.g., SYNC signals), system information (e.g., system information
blocks (SIBs)), paging information (e.g., physical broadcast
channel (PBCH) messages), or random access information (e.g.,
random access channel (RACH) signals). In some examples, all of the
wireless nodes associated with a network operating entity may
transmit at the same time during their exclusive resources.
[0054] In some examples, resources may be classified as prioritized
for certain network operating entities. Resources that are assigned
with priority for a certain network operating entity may be
referred to as a guaranteed interval (G-INT) for that network
operating entity. The interval of resources used by the network
operating entity during the G-INT may be referred to as a
prioritized sub-interval. For example, resources 335-a may be
prioritized for use by Operator A and may therefore be referred to
as a G-INT for Operator A (e.g., G-INT-OpA). Similarly, resources
335-b may be prioritized for Operator B, (e.g., G-INT-OpB),
resources 335-c (e.g., G-INT-OpC) may be prioritized for Operator
C, resources 335-d may be prioritized for Operator A, resources
335-e may be prioritized for Operator B, and resources 335-f may be
prioritized for Operator C.
[0055] The various G-INT resources illustrated in FIG. 3 appear to
be staggered to illustrate their association with their respective
network operating entities, but these resources may all be on the
same frequency bandwidth. Thus, if viewed along a time-frequency
grid, the G-INT resources may appear as a contiguous line within
the superframe 305. This partitioning of data may be an example of
time division multiplexing (TDM). Also, when resources appear in
the same sub-interval (e.g., resources 340-a and resources 335-b),
these resources represent the same time resources with respect to
the superframe 305 (e.g., the resources occupy the same
sub-interval 320), but the resources are separately designated to
illustrate that the same time resources can be classified
differently for different operators.
[0056] When resources are assigned with priority for a certain
network operating entity (e.g., a G-INT), that network operating
entity may communicate using those resources without having to wait
or perform any medium sensing procedures (e.g., LBT or CCA). For
example, the wireless nodes of Operator A are free to communicate
any data or control information during resources 335-a without
interference from the wireless nodes of Operator B or Operator
C.
[0057] A network operating entity may additionally signal to
another operator that it intends to use a particular G-INT. For
example, referring to resources 335-a, Operator A may signal to
Operator B and Operator C that it intends to use resources 335-a.
Such signaling may be referred to as an activity indication.
Moreover, since Operator A has priority over resources 335-a,
Operator A may be considered as a higher priority operator than
both Operator B and Operator C. However, as discussed above,
Operator A does not have to send signaling to the other network
operating entities to ensure interference-free transmission during
resources 335-a because the resources 335-a are assigned with
priority to Operator A.
[0058] Similarly, a network operating entity may signal to another
network operating entity that it intends not to use a particular
G-INT. This signaling may also be referred to as an activity
indication. For example, referring to resources 335-b, Operator B
may signal to Operator A and Operator C that it intends not to use
the resources 335-b for communication, even though the resources
are assigned with priority to Operator B. With reference to
resources 335-b, Operator B may be considered a higher priority
network operating entity than Operator A and Operator C. In such
cases, Operators A and C may attempt to use resources of
sub-interval 320 on an opportunistic basis. Thus, from the
perspective of Operator A, the sub-interval 320 that contains
resources 335-b may be considered an opportunistic interval (O-INT)
for Operator A (e.g., O-INT-OpA). For illustrative purposes,
resources 340-a may represent the O-INT for Operator A. Also, from
the perspective of Operator C, the same sub-interval 320 may
represent an O-INT for Operator C with corresponding resources
340-b. Resources 340-a, 335-b, and 340-b all represent the same
time resources (e.g., a particular sub-interval 320), but are
identified separately to signify that the same resources may be
considered as a G-INT for some network operating entities and yet
as an O-INT for others.
[0059] To utilize resources on an opportunistic basis, Operator A
and Operator C may perform medium-sensing procedures to check for
communications on a particular channel before transmitting data.
For example, if Operator B decides not to use resources 335-b
(e.g., G-INT-OpB), then Operator A may use those same resources
(e.g., represented by resources 340-a) by first checking the
channel for interference (e.g., LBT) and then transmitting data if
the channel was determined to be clear. Similarly, if Operator C
wanted to access resources on an opportunistic basis during
sub-interval 320 (e.g., use an O-INT represented by resources
340-b) in response to an indication that Operator B was not going
to use its G-INT (e.g., resources 335-b), Operator C may perform a
medium sensing procedure and access the resources if available. In
some cases, two operators (e.g., Operator A and Operator C) may
attempt to access the same resources, in which case the operators
may employ contention-based procedures to avoid interfering
communications. The operators may also have sub-priorities assigned
to them designed to determine which operator may gain access to
resources if more than operator is attempting access
simultaneously. For example, Operator A may have priority over
Operator C during sub-interval 320 when Operator B is not using
resources 335-b (e.g., G-INT-OpB). It is noted that in another
sub-interval (not shown) Operator C may have priority over Operator
A when Operator B is not using its G-INT.
[0060] In some examples, a network operating entity may intend not
to use a particular G-INT a ssigned to it, but may not send out an
activity indication that conveys the intent not to use the
resources. In such cases, for a particular sub-interval 320, lower
priority operating entities may be configured to monitor the
channel to determine whether a higher priority operating entity is
using the resources. If a lower priority operating entity
determines through LBT or similar method that a higher priority
operating entity is not going to use its G-INT resources, then the
lower priority operating entities may attempt to access the
resources on an opportunistic basis as described above.
[0061] In some examples, access to a G-INT or O-INT may be preceded
by a reservation signal (e.g., request-to-send (RTS)/clear-to-send
(CTS)), and the contention window (CW) may be randomly chosen
between one and the total number of operating entities.
[0062] In some examples, an operating entity may employ or be
compatible with coordinated multipoint (CoMP) communications. For
example an operating entity may employ CoMP and dynamic time
division duplex (TDD) in a G-INT and opportunistic CoMP in an O-INT
as needed.
[0063] In the example illustrated in FIG. 3, each sub-interval 320
includes a G-INT for one of Operator A, B, or C. However, in some
cases, one or more sub-intervals 320 may include resources that are
neither reserved for exclusive use nor reserved for prioritized use
(e.g., unassigned resources). Such unassigned resources may be
considered an O-INT for any network operating entity, and may be
accessed on an opportunistic basis as described above.
[0064] In some examples, each subframe 325 may contain 14 symbols
(e.g., 250-.mu.s for 60 kHz tone spacing). These subframes 325 may
be standalone, self-contained Interval-Cs (ITCs) or the subframes
325 may be a part of a long ITC. An ITC may be a self-contained
transmission starting with a downlink transmission and ending with
an uplink transmission. In some embodiments, an ITC may contain one
or more subframes 325 operating contiguously upon medium
occupation. In some cases, there may be a maximum of eight network
operators in an A-INT 310 (e.g., with duration of 2 ms) assuming a
250-.mu.s transmission opportunity.
[0065] Although three operators are illustrated in FIG. 3, it
should be understood that fewer or more network operating entities
may be configured to operate in a coordinated manner as described
above. In some cases, the location of the G-INT, O-INT, or A-INT
within the superframe 305 for each operator is determined
autonomously based on the number of network operating entities
active in a system. For example, if there is only one network
operating entity, each sub-interval 320 may be occupied by a G-INT
for that single network operating entity, or the sub-intervals 320
may alternate between G-INTs for that network operating entity and
O-INTs to allow other network operating entities to enter. If there
are two network operating entities, the sub-intervals 320 may
alternate between G-INTs for the first network operating entity and
G-INTs for the second network operating entity. If there are three
network operating entities, the G-INT and O-INTs for each network
operating entity may be designed as illustrated in FIG. 3. If there
are four network operating entities, the first four sub-intervals
320 may include consecutive G-INTs for the four network operating
entities and the remaining two sub-intervals 320 may contain
O-INTs. Similarly, if there are five network operating entities,
the first five sub-intervals 320 may contain consecutive G-INTs for
the five network operating entities and the remaining sub-interval
320 may contain an O-INT. If there are six network operating
entities, all six sub-intervals 320 may include consecutive G-INTs
for each network operating entity. It should be understood that
these examples are for illustrative purposes only and that other
autonomously determined interval allocations may be used.
[0066] It should be understood that the coordination framework
described with reference to FIG. 3 is for illustration purposes
only. For example, the duration of superframe 305 may be more or
less than 20 ms. Also, the number, duration, and location of
sub-intervals 320 and subframes 325 may differ from the
configuration illustrated. Also, the types of resource designations
(e.g., exclusive, prioritized, unassigned) may differ or include
more or less sub-designations.
[0067] The aspects described herein are directed to enhanced
resource reservation operations for shared spectrum operations,
such as in sidelink channel operations. Sidelink channel
communications involve device-to-device communications that may
occur and/or be scheduled independent of a network (e.g., base
station). In such sidelink communications, devices may
opportunistically use spectrum which is allocated for
device-to-device communication, but such spectrum is not allocated
only to a particular device. Devices may perform CCA/LBT operations
before transmitting to prevent multiple devices from accessing the
spectrum at the same time (e.g., prevent collisions and
interference).
[0068] In some networks, devices may signal their intent to
transmit and attempt to reserve resources in shared spectrum. For
example, using a sidelink message, such as SCI-1, a transmitting
device can reserve resources for up to three retransmissions in a
periodic pattern. A period of this pattern can be indicated in the
sidelink message, e.g., SCI-1. For example, a value range can be
indicated, such as 1.about.99, 100, 200, . . . , 1000, etc. A value
of 0 may indicate no periodic reservation. A message, such as
SCI-1, can be RRC configured to reserve additional slots (e.g., one
or two) within thirty-two slots of the first transmission (e.g.,
first transport block (TB) transmission).
[0069] A device (e.g., node) can be triggered to report available
resources to or in an upper layer. This information for available
resources may be determined based on a history of SCI-1 messages
received at a device. For example, a device may monitor SCI-1
messages and take into consideration the resources reserved by
other device, and optionally the priority of the monitored SCI-1
messages. For a monitored SCI-1, the device (e.g., node) will
reserve the resource for the current transmission and up to 3
retransmissions; the resources in the next instance of the
indicated period (if non-zero period indicated). For an occasion
that the device (e.g., node) cannot monitor, such as due to half
duplex restrictions, the device will assume the worst case (there
is an SCI-1 transmitted in the slot but not detected) and block the
slots possibly indicated by all periods configured (up to 15
slots).
[0070] For sidelink transmission in NR-U, Channel Occupancy Time
(COT) sharing is introduced to efficiently and effectively access a
medium when competing with other networks and/or protocols, such as
WiFi. Nodes may assist other nodes to secure a COT for them and/or
share a portion of their own reserved COT with other nodes.
[0071] However, such COT sharing may cause some unwanted effects or
drawbacks, such as increased LBT operations, increased collisions,
more advanced devices hogging the medium, etc. To alleviate one or
more of such effects, a UE may utilize the enhanced resource
reservation techniques described herein to reduce or eliminate
these effects.
[0072] As an example, networks may stipulate rules for contending
for a medium which increase potential LBT operations when COT
sharing. Such rules may include under what conditions devices
should perform particular LBT operations. To illustrate, an
initiating device may have multiple transmissions without
performing an additional CCA in the COT if the gap is less than or
equal to 16 .mu.s. Otherwise, if this gap exceeds 16 .mu.s but does
not exceed 25 .mu.s, the initiating device may continue
transmissions provided that no energy was detected with a level
above a threshold (such as perform a CAT 2 LBT operation). If there
is a more than 25 .mu.s transmission gap, the UE cannot continue
transmission with CAT 1 or 2 LBT operations and a more intensive
CAT 3 or 4 LBT operation may be required, even in a UE's own
COT.
[0073] However, the relative offsets for future RR may be
pre-assigned, e.g., dictated by the network and/or RRC configured.
Thus, in UE's own future COT, there may be a relatively long (e.g.,
greater than 25 us) transmission gap before a RR or between RRs,
and thus a CAT 4 LBT operation may be needed for retransmission in
a particular RR.
[0074] In some aspects, a transmitting device may continuously
transmit (e.g., transmits data or pad slots) in a non-shared region
of a COT with a data transmission or transmission before the
particular RR so CAT 1 or 2 LBT operation is possible. In addition,
the UE may not perform a CAT 4 LBT operation when continuously
transmitting and controlling the medium. Thus, the UE may be able
to use a less intensive LBT operation by continuously
transmitting.
[0075] As another example, in conventional networks, other UEs
cannot reserve resources in a non-shared COT region of a COT which
is reserved to another UE. However, for resource selection when
continuously transmitting (e.g., padding the slots), no subchannels
and/or slots in the non-shared COT are excluded due from
reservation. In some networks, random resource selection does not
guarantee a UE's continuous transmission. For example, random
resource selection in Release 16 may not guarantee a UE's
continuous transmission until RR1.
[0076] In some aspects, a device may utilize a multiple step
resource selection/reservation scheme to prioritize a particular
UEs RR and/or to reduce continuous transmission length. For
example, a UE may prioritize time first and then subchannel to
reserve resource before its own RR. Such a scheme may increase a
chance of continuous transmission for the UE and/or may reduce a
size of continuous transmission for the UE.
[0077] In some aspects, a device may adjust or reconfigure a COT to
reduce or eliminate continuous transmission. For example, a UE may
reduce a size of a shared COT region and increase a size of a
non-shared COT region to prioritize its own RR. In some
implementations, the non-shared COT region is extended to cover a
last RR of the UE.
[0078] Additionally, or alternatively, in some aspects a device may
reserve a dedicated subchannel in their own COT to maintain
continuous transmission. A reserved subchannel may exclude other
UEs from resource selection or reservation in the COT or a portion
thereof (e.g., the non-shared COT region or the shared COT region).
The UE owning the COT may prioritize the reserved subchannel for
transmissions which occur before one or more of the RRs. Earlier
slots within reserved subchannel are also prioritized. In a
particular implementation, the COT owning UE may continuous
transmit packets before a RR in the shared COT region. In some
implementations, a COT owning UE may also refrain from reserving
resources in non-reserved subchannels. In a particular
implementation, a portion of the COT may include LBT gaps in the
reserved subchannel so that other UEs can clear LBT processes and
transmit in other subchannels.
[0079] In some aspects, a device may adjust a quality threshold
used to determine available resources, referred to as candidate
resources, for resource selection. For example, the device may
adjust or select a higher or lower reference signal received power
(RSRP) threshold to increase or decrease the chances of reserving a
resource. To illustrate, adjusting the threshold may make some
resources available to the UE or restrict some resources from the
UE in an attempt to accommodate less advanced UEs, such as single
step or random resource selection UEs.
[0080] Additionally or alternatively, in some aspects a device may
move one or more RRs. Specifically, a UE may move its own RR or an
RR of another UE to accommodate COT sharing. For example, a UE may
move its own RR to reduce or eliminate continuous transmission
(e.g., padding). To illustrate, a UE may move one or more RRs to an
earlier slot. As another example, a UE may move a RR of another UE
to prevent a possible RR collision.
[0081] In some implementations, moving a RR of another UE may
involve sending a new sidelink transmission. For example, the UE
may use a new SCI-2 message. To illustrate, the SCI-2 message may
have a different format than conventional sidelink messages or
SCI-2 messages. In a particular implementation, the SCI-2 message
may include additional information or fields to relocate a RR of
another UE.
[0082] FIG. 4 illustrates an example of a wireless communications
system 400 that supports enhanced resource reservation for sidelink
communications in accordance with aspects of the present
disclosure. In some examples, wireless communications system 400
may implement aspects of wireless communication system 100. For
example, wireless communications system 400 may include UEs 115 and
415. Enhanced resource reservation for sidelink communications
operations may reduce network overhead and latency and increase
throughput. Thus, network and device performance can be
increased.
[0083] UE 115 and 415 may be configured to communicate via
frequency bands, such as FR1 having a frequency of 410 to 7125 MHz,
FR2 having a frequency of 24250 to 52600 MHz for mm-Wave, and/or
one or more other frequency bands. It is noted that SCS may be
equal to 15, 30, 60, or 120 kHz for some data channels. UE 115 and
415 may be configured to communicate via one or more component
carriers (CCs), such as representative first CC 481, second CC 482,
third CC 483, and fourth CC 484. Although four CCs are shown, this
is for illustration only, more or fewer than four CCs may be used.
One or more CCs may be used to communicate control channel
transmissions, data channel transmissions, and/or sidelink channel
transmissions.
[0084] Such transmissions may include a Physical Downlink Control
Channel (PDCCH), a Physical Downlink Shared Channel (PDSCH), a
Physical Uplink Control Channel (PUCCH), a Physical Uplink Shared
Channel (PUSCH), a Physical Sidelink Control Channel (PSCCH), a
Physical Sidelink Shared Channel (PSSCH), or a Physical Sidelink
Feedback Channel (PSFCH). Such transmissions may be scheduled by
aperiodic grants and/or periodic grants.
[0085] Each periodic grant may have a corresponding configuration,
such as configuration parameters/settings. The periodic grant
configuration may include configured grant (CG) configurations and
settings. Additionally, or alternatively, one or more periodic
grants (e.g., CGs thereof) may have or be assigned to a CC ID, such
as intended CC ID.
[0086] Each CC may have a corresponding configuration, such as
configuration parameters/settings. The configuration may include
bandwidth, bandwidth part, Hybrid automatic repeat request (hybrid
ARQ or HARQ) process, TCI state, RS, control channel resources,
data channel resources, or a combination thereof. Additionally, or
alternatively, one or more CCs may have or be assigned to a Cell
ID, a Bandwidth Part (BWP) ID, or both. The Cell ID may include a
unique cell ID for the CC, a virtual Cell ID, or a particular Cell
ID of a particular CC of the plurality of CCs. Additionally, or
alternatively, one or more CCs may have or be assigned to a HARQ
ID. Each CC may also have corresponding management functionalities,
such as, beam management, BWP switching functionality, or both. In
some implementations, two or more CCs are quasi co-located, such
that the CCs have the same beam and/or same symbol.
[0087] In some implementations, control information may be
communicated via UE 115 and 415. For example, the control
information may be communicated suing MAC-CE transmissions, RRC
transmissions, DCI, transmissions, another transmission, or a
combination thereof.
[0088] UE 115 can include a variety of components (e.g.,
structural, hardware components) used for carrying out one or more
functions described herein. For example, these components can
includes processor 402, memory 404, transmitter 410, receiver 412,
encoder, 413, decoder 414, continuous transmission manager 415,
resource selector 416, and antennas 252a-r. Processor 402 may be
configured to execute instructions stored at memory 404 to perform
the operations described herein. In some implementations, processor
402 includes or corresponds to controller/processor 280, and memory
404 includes or corresponds to memory 282. Memory 404 may also be
configured to store resources data 406, reserved resources data
408, transmission data 442, settings data 444, or a combination
thereof, as further described herein.
[0089] The resources data 406 includes or corresponds to data
associated with or corresponding to available resources. For
example, the resources data 406 may indicate candidate resources
(e.g., available resources) of a candidate resource set. The
resources data 406 may also include thresholds or data used to
evaluate the resources selection conditions, such as conditions for
candidate resources. Additionally, the resources data 406 may also
include thresholds or data used to evaluate resources selection
conditions for certain COT conditions. The resources data 406 may
further include COT data. For example, the COT data may include COT
configurations, COT adjustment conditions, COT allocations,
etc.
[0090] The RR data 408 includes or corresponds to data indicating
or corresponding to RR for data transmissions. For example, the RR
data 408 may include RRs for particular transmission (e.g.,
particular TB). The RR data 408 may also include parameters or
settings for determining RRs and/or selecting or prioritizing
resources. For example, the RR data 408 may include network
configured or pre-configured settings for RR location and period.
As another example, the RR data may include data for a two-step
selection process.
[0091] The transmission data 442 includes or corresponds to data
that is associated with data transmissions for sidelink channels.
The transmission data 442 may include data transmissions and
retransmissions for sidelink channels.
[0092] The settings data 444 includes or corresponds to data
associated with enhanced resource reservation operations. The
settings data 444 may include one or more types of resource
reservation operation modes and/or thresholds or conditions for
switching between resource reservation modes and/or configurations.
For example, the settings data 444 may have data indicating
different thresholds for different resource reservation modes, such
as UE single step resource selection and two-step resource
selection.
[0093] Transmitter 410 is configured to transmit data to one or
more other devices, and receiver 412 is configured to receive data
from one or more other devices. For example, transmitter 410 may
transmit data, and receiver 412 may receive data, via a network,
such as a wired network, a wireless network, or a combination
thereof. For example, UE 115 may be configured to transmit and/or
receive data via a direct device-to-device connection, a local area
network (LAN), a wide area network (WAN), a modem-to-modem
connection, the Internet, intranet, extranet, cable transmission
system, cellular communication network, any combination of the
above, or any other communications network now known or later
developed within which permits two or more electronic devices to
communicate. In some implementations, transmitter 410 and receiver
412 may be replaced with a transceiver. Additionally, or
alternatively, transmitter 410, receiver, 412, or both may include
or correspond to one or more components of UE 115 described with
reference to FIG. 2.
[0094] Encoder 413 and decoder 414 may be configured to encode and
decode data for transmission. Continuous transmission manager 415
may be configured to determine and perform continuous transmission
operations. For example, continuous transmission manager 415 is
configured to determine when to use continuous transmission. As
another example, continuous transmission manager 415 is configured
to generate packets for continuous transmission. In some
implementations, the continuous transmission manager 415 ix
configured to generate padding data to pad one or more slots of the
continuous transmission
[0095] Resource selector 416 may be configured to determine and
perform resource selection operations. For example, resource
selector 416 may be configured to determine available resources,
prioritize available resources, and reserve resources.
[0096] UE 415 includes processor 430, memory 432, transmitter 434,
receiver 436, encoder 437, decoder 438, continuous transmission
manager 439, resource selector 440, and antennas 234a-t. Processor
430 may be configured to execute instructions stores at memory 432
to perform the operations described herein. In some
implementations, processor 430 includes or corresponds to
controller/processor 240, and memory 432 includes or corresponds to
memory 242. Memory 432 may be configured to store resource data
406, RR data 408, transmission data 442, settings data 444, or a
combination thereof, similar to the UE 115 and as further described
herein.
[0097] Transmitter 434 is configured to transmit data to one or
more other devices, and receiver 436 is configured to receive data
from one or more other devices. For example, transmitter 434 may
transmit data, and receiver 436 may receive data, via a network,
such as a wired network, a wireless network, or a combination
thereof. For example, UE 415 may be configured to transmit and/or
receive data via a direct device-to-device connection, a local area
network (LAN), a wide area network (WAN), a modem-to-modem
connection, the Internet, intranet, extranet, cable transmission
system, cellular communication network, any combination of the
above, or any other communications network now known or later
developed within which permits two or more electronic devices to
communicate. In some implementations, transmitter 434 and receiver
436 may be replaced with a transceiver. Additionally, or
alternatively, transmitter 434, receiver, 436, or both may include
or correspond to one or more components of UE 415 described with
reference to FIG. 2.
[0098] Encoder 437, and decoder 438 may include the same
functionality as described with reference to encoder 413 and
decoder 414, respectively. Continuous transmission manager 439 may
include similar functionality as described with reference to
continuous transmission manager 415. Resource selector 440 may
include similar functionality as described with reference to
resource selector 416.
[0099] During operation of wireless communications system 400, UE
415 may determine that UE 115 has enhanced resource reservation
capability. For example, UE 115 may transmit a message 448 that
includes an enhanced resource reservation indicator 490 (e.g.,
two-step resource selection indicator). Indicator 490 may indicate
enhanced resource reservation operation capability or a particular
type or mode of resource reservation operation. In some
implementations, UE 415 sends control information to indicate to UE
115 that enhanced resource reservation operation and/or a
particular type of enhanced resource reservation operation is to be
used. For example, in some implementations, message 448 (or another
message, such as configuration transmission 450) is transmitted by
the UE 415 or a network entity. The configuration transmission 450
may include or indicate to use enhanced resource reservation
operations or to adjust or implement a setting of a particular type
of enhanced resource reservation operation.
[0100] During operation, devices of wireless communications system
400, perform enhanced resource reservation operations. For example,
the UEs 115 and 415 exchange transmissions via a sidelink channel.
In the example of FIG. 4, the UE 415 transmits a sidelink channel
control message 452 to the UE 115. The sidelink channel control
message 452 may include or indicate a particular resource selected
by the UE 415 for reservation. To illustrate, the UE 415 may send a
SCI message indicating the resource.
[0101] The UE 115 may receive the sidelink channel control message
452 and may determine the particular resource reserved by the UE
415. In some implementations, the UE 115 may determine to relocate
the selected resource release based on the resource overlapping or
colliding with a RR of the UE 115. The RR of the UE 115 may
correspond to a retransmission of a prior transmission in some
implementations.
[0102] In such implementations where the UE 115 determines to
relocate the selected resource, the UE 115 may send a sidelink
channel control message 454 to relocate the selected resource.
Additionally, or alternatively, the UE 115 transmits the sidelink
channel control message 454 to indicate one or more RRs of the UE
115.
[0103] The UEs 115 and 415 may then transmit data based on the
sidelink channel control message 452 and/or 454. For example, the
UE 115 may transmit a sidelink channel data transmission 456, and
the UE 415 may optionally transmit a sidelink channel data
transmission 458. The UE 115 may continuously transmit and/or pad
one or more slots prior to the sidelink channel data transmission
456 to prevent another UE (e.g., 415) from transmitting prior to
the UE 115. Thus, the UE 115 may perform a reduced or no LBT
operation (e.g., CAT 1 or 2 LBT operation) prior to transmitting
the sidelink channel data transmission 456.
[0104] Accordingly, the UEs 115 and 415 may be able to more
efficiently perform resource reservation operations. Thus, FIG. 4
describes enhanced resource reservation operations. Using enhanced
resource reservation operations may enable improvements when
operating in shared spectrum. Performing enhanced resource
reservation enables reduced bandwidth/spectrum waste when
performing contention operations and thus, enhanced UE and network
performance by increasing throughput and reducing latency.
[0105] FIG. 5 is a diagram illustrating an example of continuous
transmission operations. In FIG. 5, a plurality of COTs are
illustrated. Specifically, two COTs are depicted with both COTs
reserved or allocated to a first UE. Each of the reserved COTs may
include a non-shared region and a shared region. In other
implementations, one or more other COTs may occur between the two
COTs, that is between COTs reserved to the first UE.
[0106] FIG. 5 depicts resources reserved for multiple UEs, first,
second, and third UEs. A first UE (UE 1) may have or be associated
with a plurality of reserved resources (RRs) for a later COT which
correspond to a first transmission in a first COT. In the example
of FIG. 5, the first UE is associated with two future RRs (RR1 and
RR2). A first RR (RR1) is located in a non-shared portion of the
COT, and a second RR (RR2) is located in a shared portion of the
COT. A second UE (UE 2) has a transmission (e.g., RR) in the shared
portion of the COT and a third UE (UE 3) has a RR (UE 3 RR2) in the
shared portion of the COT.
[0107] The RRs for the first UE may be pre-assigned based on
network and/or device settings. Also, such RRs may include RRs
(e.g., UE 1 RR1 and RR2) which are located more than 25 .mu.s into
the COT. Thus, as other UE's may schedule and transmit in the
portion prior to the RR, the first UE may need to perform a LBT
operation, such as a CAT 4 LBT operation, prior to transmitting in
the RR.
[0108] To eliminate such an occurrence, the first UE may engage in
continuous transmission to reduce or eliminate LBT operations. For
example, the first UE may transmit other data or continuously pad
the slots in the non-shared COT region with UE's data transmission
before the first RR so a CAT 1 or 2 LBT operation is possible. To
illustrate, a CAT 1 or 2 LBT operation is performed right before
the first RR or at a start of the first RR. In some
implementations, a prior and/or full LBT operation may occur prior
to the reduced LBT operation for the first RR. For example, the UE
may perform a CAT 3 or 4 operation at a start of the non-shared
portion as illustrated in FIG. 5 to secure the medium for the
continuous transmission and the first RR transmission.
[0109] Additionally, or alternatively, the first UE continuously
transmits between the first RR and the second RR. For example, the
first UE may continuously pad the slots between the first RR and
the second RR. However, such long padding may not be possible
(e.g., UE buffer size limitation) or a transmission gap is
unavoidable due to previous reserved resources. In addition, such
long padding ties up the medium, which may not be compatible with
other networks and/or protocols (e.g., WiFi), and reduces
throughput.
[0110] In other implementations, the first UE may adjust the shared
COT region so that non-shared COT region covers its own next and/or
last RR. For example, the first UE may protects its own RR by
downsizing the shared COT region to prioritize its own RR without
additional padding (e.g., padding between RR1 and RR2). Additional
alternatives to extra padding are described with reference to FIG.
7.
[0111] FIG. 6 is a diagram illustrating an example of two-step
resource selection. In FIG. 6, a resource selection window (RSW) is
illustrated. The RSW illustrates resources of a COT for a UE where
rows correspond to time slots and columns correspond to channels.
To illustrate, the RSW illustrates six time slots for four
different subchannels. As illustrated in FIG. 6, the UE includes a
RR (e.g., RR1) in a sixth slot and a first channel.
[0112] In FIG. 6, white box resources are candidate resources which
belong to a candidate resource set, and grey box resources are
unavailable resources or non-candidate resources. As previously
described, resources are evaluated based on a quality condition or
criterion, such as RSRP; candidate resources satisfy the quality
condition or criterion. For example, the candidate resources are
resources which have a RSRP below a RSRP threshold.
[0113] The candidate resource set may be reported to higher layers
and/or other devices. In conventional, single step (e.g., random
resource selection), candidate resources are selected randomly from
the candidate resource set and are reserved or selected for
reservation.
[0114] In the example of FIG. 6, a two-step resource selection
process is illustrated which is based on time and subchannel. For
example, the two-step resource selection may prioritize candidate
resources from the candidate resource set with earlier times first
and then prioritize the candidate resources based on subchannels
second. To illustrate, a UE may select candidate resources with
times before its own RR and then based on a subchannel priority
(e.g., lower subchannels, higher subchannels, or subchannel
priority index, etc.).
[0115] In such two-step resource selection processes, a UE may
start with a first slot within the candidate resource set, and then
a second slot, and then a third slot, and so on. After filling up
the slots in time order, the UE may then continue assigning the
slots for the next available subchannel.
[0116] To illustrate, with respect to the RSW of FIG. 6, the UE
assigns a first slot (e.g., leftmost slot) in a first subchannel
(e.g., bottommost channel) as a first resource (e.g., resource 0).
The UE may then assign a second resource (e.g., 1) in a second
slot. As the only available resource of the second slot which is
available is in a fourth or lowest priority subchannel, the UE
assigns the second slot in the fourth subchannel as the second
resource (e.g., 1). The UE then continues assigning resources in
the first subchannel for third through fifth slots, as such slots
are available. The UE then skips the sixth time slot for assigning
resource priorities because the RR for the UE is scheduled for the
sixth slot. The UE then reverts back to the first slot for the
sixth resource (e.g., 5) which is in the third subchannel because
the second subchannel is not available for the first slot. Such
two-step schemes and other schemes which prioritize earlier times
increase earlier resource reservation and reduce possible
continuous transmission durations.
[0117] FIG. 7 is a diagram illustrating another example of
continuous transmission operations. In FIG. 7, a plurality of COTs
are illustrated. Specifically, two COTs are depicted with both COTs
reserved or allocated to a first UE. Each of the reserved COTs may
include a non-shared region and a shared region. In other
implementations, one or more other COTs may occur between the two
COTs, that is between COTs reserved to the first UE.
[0118] FIG. 7 depicts resources reserved for multiple UEs, first,
second, and third UEs. A first UE (UE 1) may have or be associated
with a plurality of reserved resources (RRs) for a later COT which
corresponds to a first transmission in a first COT. In the example
of FIG. 7, the first UE is associated with two future RRs (RR1 and
RR2). Both RRs (RR1 and RR2) are located in a shared portion of the
second COT. A second UE (UE 2) has a transmission (e.g., RR) in the
shared portion of the second COT and a third UE (UE 3) has a RR (UE
3 RR2) in the shared portion of the second COT.
[0119] The RRs for the first UE may be pre-assigned based on
network and/or device settings. Also, such RRs may include RRs
(e.g., UE 1 RR1 and RR2) which are located more than 25 .mu.s into
the second COT or a portion of the second COT. Thus, as other UE's
may schedule and transmit in the portion prior to the RRs, the
first UE may need to perform a LBT operation, such as a CAT 4 LBT
operation.
[0120] To eliminate such an occurrence, the first UE may engage in
continuous transmission to reduce or eliminate LBT operations, as
described with reference to FIG. 5. Alternatively, a dedicated
reserved subchannel for a COT owning UE (e.g., first UE) may be
used to maintain continuous transmission as illustrated in FIG. 7.
In the example of FIG. 7, a fourth subchannel (e.g., topmost row)
is reserved to the first UE which reserved or was allocated the
second COT. A reserved subchannel is excluded from resource
selection or reservation by other UE's in the non-shared and shared
COT regions. Thus, only the first UE may transmit in the reserved
subchannel.
[0121] A UE owning the COT will prioritize the reserved subchannel
before other subchannels. The UE may also prioritize slots in the
reserved subchannel before the RRs. In addition, earlier slots
within reserved subchannel may also be prioritized. The COT owning
UE may continuously transmit packets before the RR or RRs in the
reserved subchannel in the shared COT region. The UE may also
continuously transmit packets in the reserved subchannel in the
non-shared COT region.
[0122] In some implementations, the COT owning UE may also refrain
from reserving resources (e.g., RRs) in reserved subchannel.
Otherwise, if there are more than one RR in the shared COT region,
UE may transmit a new TB on the first RR when there is no
retransmission in order to maintain continuous transmission until a
second (e.g., next) RR.
[0123] Additionally, or alternatively, the reserved subchannel may
include LBT gaps. For example, one or more slots of the reserved
channel may include a LBT gap. To illustrate, in the example of
FIG. 7 each slot in the reserved subchannel of the non-shared COT
region includes a LBT gap. The LBT gap enables other UEs to clear
the LBT gap (e.g., successfully perform a LBT operation) and
transmit in other subchannels.
[0124] In some implementations, other subchannels may include one
or more LBT gaps. Additionally or alternately, although the LBT
gaps are only present in the shared portion of the second COT
(shared COT region), the non-shared COT region may include one or
more LBT gaps in other implementations.
[0125] FIG. 8 is a diagram illustrating an example of resource
relocation. In FIG. 8, a plurality of COTs are illustrated.
Specifically, three COTs are depicted with first and third COTs
reserved or allocated to a first UE (UE 1) and a second a COT
reserved or allocated to a second UE (UE 2). Each of the reserved
COTs may include a non-shared region and a shared region. In other
implementations, one or more other COTs may occur between the first
and third COTs, that is between COTs reserved to the first UE.
[0126] FIG. 8 depicts "special handling" for reserved resources for
a UE within their own COT. That is, a UE may adjust the COT itself
or adjust where the reserved resources occur within the COT.
[0127] As an example of adjusting the COT itself, the first UE may
enlarge the non-shared portion of the COT, reduce the shared
portion of the COT, or eliminate the shared portion of the COT.
Accordingly, the UE may prevent or reduce other devices from being
able to reserve resources in the first UE's COT.
[0128] As an example of resource relocation for the UE itself, the
UE may move (e.g., relocate) one or more of its own reserved
resources. For example, the first UE may move one or more resources
earlier in the COT, such as from the shared region to the
non-shared region of the COT. To illustrate, a first and second
reserved resource for the UE may be moved from the shared region to
the non-shared region of the COT.
[0129] In the example of FIG. 8, the first UE also may have other
data to send, such a data corresponding to a new, second TB. In
some implementations, the first UE may transmit the new second TB
in a first slot of the non-shared portion of the COT.
[0130] In some such implementations, the UE may move a RR to the
same slot of the new TB. The RR may be frequency division
multiplexed on a different subchannel or to the slot immediately
after the last new TB or TBs. In such implementations, no
additional LBT is required since the retransmission is a continuous
transmission within the UE's non-shared portion of COT.
[0131] If the original RR is in the shared COT region, as indicated
by SI-COT, the RR is treated as cancelled by the other UEs. Other
UEs monitoring the SI-COT could figure out the starting position of
the shared COT region and the source UE's RR in the shared COT
region is treated cancelled. In some implementations, the other UE
can reserve on the cancelled RR if the timeline permits.
[0132] The new locations of RRs are within the non-shared COT
region and are up to the transmitting node scheduling decision. As
other nodes do not put RRs in the non-shared COT region for
two-step (e.g. 2-stage) resource reservation, the source UE can
schedule retransmission anywhere within the non-shared COT
region.
[0133] FIG. 9 is a diagram illustrating an example of in and out of
COT priority for resource selection. In FIG. 9, a sensing window
and a non-shared COT region are illustrated.
[0134] Referring back to the RSW of FIG. 6, the quality condition
or criterion for determining available resources may be adjusted
based on whether the resource falls within a COT of the UE or
outside of COT of the UE. For example, when a UE is performing
resource selection for resources which falls out-of-COT (e.g.,
outside of its own COT or inside another UE's non-shared COT
region), the quality condition or criterion could be set or
adjusted (e.g., higher) so that the other UE which checks out the
COT (e.g., COT owning UE) has higher probability utilizing the
resource. To illustrate, the RSRP threshold could be higher so that
the other UE which checks out the COT has a higher probability of
utilizing the resource. However, in the shared COT region, other
UEs may recognize the shared COT region has higher priority over
some UEs which do not recognize the shared COT region. Thus, legacy
reserved resources reserved by legacy devices with an absolute
offset may have lower priority.
[0135] In a particular implementation, legacy UE's, one-step
resource selection UE's, random resource selection UE's, etc., may
utilize higher thresholds to have an increased chance of the RSRP
being below the threshold and that such resource will be available
for resource selection. To illustrate, if the RSRP threshold is
raised, a particular (e.g., legacy) UE may be able to reserve one
or more of the grey box resources, non-candidate resources, of FIG.
6 which are unavailable to another UE (e.g., two-step resource
selection UE).
[0136] Additionally, or alternatively, other types of UE's (e.g.,
two-step resource selection UE's) may utilize adjusted quality
conditions or criteria. For example, a RSRP threshold could be
lower for a particular UE and thus resources can be excluded from
the resource selection with higher probability. The adjusted
quality condition or criterion may apply to all resource selection
or only to resource selection that falls within the UE's own COT.
In some such implementations, the adjusted quality condition or
criterion may apply to the shared region, the non-shared region, or
both.
[0137] An example illustration of such within COT and out-of-COT
priority is illustrated in FIG. 9. RSRP values may be measured
during a sensing window as illustrated in FIG. 8. In the example of
FIG. 9, a second UE and a third UE (UE 3) performing sensing
operations. Each UE then determines (e.g., estimates, approximates,
extrapolates) projected RSRPs for future resources and
selection/reservation thereof.
[0138] Based on the sensing operations and the determined projected
future RSRPs, the second UE attempts to reserve a resource in the
first UE's non-shared COT region, and the third UE also attempts to
reserve a resource in the first UE's non-shared COT region. Such
attempts may result in a success or result in a success more often
as the second and third UEs may be able to select from resources
which are not available to the first UE due to the devices using
different RSRP thresholds for determining available resources.
[0139] FIG. 10 is a diagram illustrating another example of
resource relocation. In FIG. 10, a COT for a particular UE (a first
UE, UE 1) is illustrated. The reserved COT includes a non-shared
region and a shared region.
[0140] In some instances, a particular device may not succeed in
reserving a resource out-of-COT, that is in the example of FIG. 10,
reserving a resource in the non-shared COT region. For example, the
device may not succeed even if adjusted or alternative RSRP
thresholds were used to determine available resources (e.g.,
candidate resources). In such cases, a UE (e.g., two-step resource
selection UE) may be able to relocate a resource for another UE
(e.g., a legacy UE). To illustrate, the first UE may be able to
relocate a RR for another UE from the non-shared COT region to the
shared COT region.
[0141] As illustrated in the example of FIG. 10, the second UE's RR
is scheduled for the same resource, slot and subchannel, as a RR
for the first UE. The first UE may determine such a collision will
occur and relocate the RR for the second UE. For example, the first
UE may determine that itself and another UE (second UE) have both
attempted to reserve the same resource based on receiving a message
(e.g., SCI-1) from the other UE. The first UE may select another
resource for the RR of the second UE, randomly, based on a two-step
process, or another process. The first UE may then send a message
or messages (e.g., SCI-1 and/or SCI-2) to the other UE to inform
the other UE that the resource has been moved (e.g., relocated). As
illustrated in the example of FIG. 10, the message(s) may be sent
prior to the RR of the second UE, such as the first time slot of
the non-shared COT region.
[0142] Alternatively, the first UE may determine to not move the RR
for the third UE based on the RR for the third UE not colliding
with a RR for the first UE and/or based on the RR for the third UE
occurring far enough before the RR for the first UE.
[0143] In some implementations, some a RR SCI-1 (e.g., legacy RR
SCI-1) indicates a location of one or more RRs in terms of absolute
slot offset and subchannel. For example, the RR SCI-1 may include a
field for absolute slot offset and a field for subchannel.
[0144] In some implementations, when the UE blocks another UE's
legacy RR in its own non-shared COT region, the UE may reserve a RR
in the shared COT region on other UE's behalf based on relocation
signaling which may be via RR SCI-1 in combination with a new SCI-2
format.
[0145] For example, the RR SCI-1 may indicate the slot offset and
subchannel for the relocated legacy RR. The devices may then move
the legacy RR into the shared COT region. By decoding the
relocation RR SCI-1 in the non-shared COT region, additional other
UEs that intend to transmit in shared COT region may respect the
relocated legacy RR.
[0146] A single relocation SCI-1 may be configured to relocate one
or more legacy RRs associated with a single HARQ ID within the
non-shared COT region. Multiple SCI-1's may be configured to
relocate multiple set of RRs associated with multiple HARQ ID.
[0147] In some implementations, a new SCI-2 format may be used to
indicate details of the relocation to transmitting and receiving
nodes. The new SCI-2 format may include a source ID filed which
indicates a transmitting UE ID for the reservation, a destination
ID field which indicates the receiving UE ID for the reservation, a
HARQ ID field which indicates that the RR (or RRs) associated with
specific HARQ ID has been relocated.
[0148] In some implementations, a transmitting and receiving pair
may have multiple sets of legacy RRs associated with different HARQ
IDs in the same non-shared COT region. The HARQ ID (as indicated by
the HARQ ID field) may be used to indicate which set of legacy RRs
is to be relocated.
[0149] Additionally, or alternatively, one or more operations of
FIGS. 4-10 may be added, removed, substituted in other
implementations. For example, in some implementations, the example
steps of FIGS. 5 and 7 may be used together. To illustrate, the
continuous transmission of FIG. 5 may be used with the reserved
subchannel of FIG. 7. As another example, some of the steps of
two-step resource selection of FIG. 6 may be used with any of FIGS.
4, 5, and 7-10.
[0150] FIG. 11 is a flow diagram illustrating example blocks
executed by a UE configured according to an aspect of the present
disclosure. The example blocks will also be described with respect
to UE 115 as illustrated in FIG. 13. FIG. 11 is a block diagram
illustrating UE 115 configured according to one aspect of the
present disclosure. UE 115 includes the structure, hardware, and
components as illustrated for UE 115 of FIG. 2. For example, UE 115
includes controller/processor 280, which operates to execute logic
or computer instructions stored in memory 282, as well as
controlling the components of UE 115 that provide the features and
functionality of UE 115. UE 115, under control of
controller/processor 280, transmits and receives signals via
wireless radios 1300a-r and antennas 252a-r. Wireless radios
1300a-r includes various components and hardware, as illustrated in
FIG. 2 for UE 115, including modulator/demodulators 254a-r, MIMO
detector 256, receive processor 258, transmit processor 264, and TX
MIMO processor 266. As illustrated in the example of FIG. 13,
memory 282 stores Resource Selection logic 1302, Resource
Reservation logic 1303, Continuous Transmission logic 1304,
Candidate Resources data 1305, Reserved Resources data 1306, and
settings data 1307.
[0151] At block 1100, a wireless communication device, such as a
UE, transmit a first transmission in a first Channel Occupancy Time
(COT) for a NR-U sidelink channel. For example, the UE 115 is
operating in a sidelink communication mode and transmits a sidelink
transmission, as described with reference to FIGS. 4-10. The
sidelink transmission may include or correspond to a PSSCH
transmission to another UE and the transmission may be sent in a
COT that is reserved to the UE. Alternatively, the transmission may
occur in a COT that is reserved to another UE.
[0152] Optionally, the UE 115 reserves a resource in a non-shared
portion of a second COT.
[0153] For example, the UE 115 reserves a candidate resource in a
second COT that is reserved or allocated to the UE, as described
with reference to FIGS. 4-7. The resource may be selected and/or
reserved based on reserved resource settings; such settings may be
RRC configured or pre-set. Alternatively, the resource may be
selected based on a resource selection scheme, such as a one-step
(e.g., random) selection scheme or a multi-step selection scheme
(e.g., two-step scheme based on time and subchannel priority), as
described with reference to FIGS. 4, 6, and 9.
[0154] At block 1101, the UE 115 performs a Listen-Before-Talk
(LBT) Category (CAT) 4 operation at a start of the second COT. For
example, the UE 115 performs a full LBT operation, such as a LBT
CAT 4 operation, at the start of the UE's own second COT. The
second COT may be reserved by and/or assigned to the UE 115.
[0155] At block 1102, the UE 115 performs a continuous transmission
operation in the second COT based on successfully performing the
LBT CAT 4 operation, the second COT associated with the UE. For
example, the UE 115 continuously transmits data (e.g., packets)
from a start of the second COT even if the resources were not
reserved, as described with reference to FIGS. 4-10. The continuous
transmission may occur until a RR of the UE or until shortly before
the RR of the UE, such as a first RR of the second COT (e.g., RR1).
In some implementations, the continuous transmission operation
(e.g., continuously transmitting data) includes or leaves small
gaps for channel sensing (e.g., 16 .mu.s LBT gaps) for a second
transmitter to join during the UE 115's continuous transmission
(contiguous transmission), as described in FIG. 7. In some other
implementations, the second transmitter may join without performing
a channel sensing (e.g., LBT) operation. For example, the second
transmitter may transmit in the second COT without performing a LBT
operation and the continuous transmission by the UE 115 may not
leave small gaps (e.g., LBT gaps) for channel sensing
operations.
[0156] At block 1103, the UE 115 transmits a second transmission in
a reserved resource of a non-shared portion of the second COT based
on successfully performing a second LBT CAT 1 or 2 operation. For
example, the UE 115 performs a reduced LBT operation, such as a LBT
CAT 1 or 2 operation, as described with reference to FIGS. 4-7,
during or after the continuous transmission and right before the RR
of the non-shared portion of the second COT. The UE 115 may then
perform the second transmission in the RR without performing
another full LBT CAT operation, such as a CAT 3 or 4 LBT operation,
as described with reference to FIGS. 4-10.
[0157] The UE 115 may execute additional blocks (or the UE 115 may
be configured further perform additional operations) in other
implementations. For example, the UE 115 may perform one or more
operations described above. As another example, the UE 115 may
perform one or more aspects as described below.
[0158] In a first aspect, performing the continuous transmission
operation includes continuously transmitting from after the LBT CAT
4 operation to at least a start of a shared portion of the second
COT based on successfully performing the LBT CAT 4 operation.
[0159] In a second aspect, alone or in combination with the first
aspect, continuously transmitting further includes continuously
transmitting in the shared portion of the second COT while leaving
one or more LBT gaps.
[0160] In a third aspect, alone or in combination with one or more
of the above aspects, the LBT gap is less than or equal to 16 .mu.s
or less than or equal 25 .mu.s. In other aspects, the LBT gap size
is set based on channel sensing operations, and is configured to
enable other devices to perform reduced channel sensing operations
to clear the medium and begin transmitting.
[0161] In a fourth aspect, alone or in combination with one or more
of the above aspects, performing the continuous transmission
operation further includes continuously transmitting in the shared
portion of the second COT without leaving one or more LBT gaps.
[0162] In a fifth aspect, alone or in combination with one or more
of the above aspects, the second COT includes the non-shared
portion and a shared portion, wherein the shared portion occurs
after the non-shared portion, and wherein the non-shared portion of
the second COT is reserved by the UE.
[0163] In a sixth aspect, alone or in combination with one or more
of the above aspects, the UE 115 further reserves a resource in the
non-shared portion of the second COT to claim the reserved
resource, and the second transmission corresponds to a
retransmission of the first transmission or a new transmissions of
a new transmission block (TB).
[0164] In a seventh aspect, alone or in combination with one or
more of the above aspects, reserving the resource includes:
determining available resources of a resource selection window
(RSW) which occurs before a next reserved resource (RR) for the UE;
selecting a first set of available resources from the available
resources based on an earliest time; and selecting a particular
resource of the first set of available resources based on a highest
priority subchannel for the second transmission.
[0165] In an eighth aspect, alone or in combination with one or
more of the above aspects, determining the available resources
includes: determining, a RSRP for each resource of the RSW; and
comparing each RSRP for each resource to a RSRP threshold, wherein
the available resources correspond to resources where the RSRP is
less than or equal to the RSRP threshold.
[0166] In a ninth aspect, alone or in combination with one or more
of the above aspects, determining the available resources further
includes: determining one or more unavailable resources of the RSW
based on the RSRP being greater than the RSRP threshold.
[0167] In a tenth aspect, alone or in combination with one or more
of the above aspects, reserving the resource includes: determining,
by the UE, available resources of a resource selection window (RSW)
which occurs before a next reserved resource (RR) for the UE;
assigning, by the UE, a priority to each available resource based
on an earliest time and based on a highest priority subchannel for
the RSW; and selecting, by the UE, a particular resource based on
an assigned priority, wherein earlier times and particular
subchannels are associated with higher priority.
[0168] In an eleventh aspect, alone or in combination with one or
more of the above aspects, reserving the resource includes:
determining available resources of a resource selection window
(RSW) which occurs before a next reserved resource (RR) for the UE;
assigning a priority to each available resource based on an
earliest time and based on a highest priority subchannel for the
RSW; and selecting a particular available resource based on an
earliest time with time-division multiplexing on a first priority
subchannel available.
[0169] In a twelfth aspect, alone or in combination with one or
more of the above aspects, reserving the resource includes:
determining available resources of a resource selection window
(RSW) which occur before a next reserved resource (RR) for the UE;
assigning a priority to each available resource of a first priority
subchannel based on earliest time; and assigning a priority to
available resources of a second priority subchannel based on
earliest time.
[0170] In a thirteenth aspect, alone or in combination with one or
more of the above aspects, a second apparatus transmits before a
second reserved resource (RR) of the apparatus in a shared portion
of the second COT.
[0171] In a fourteenth aspect, alone or in combination with one or
more of the above aspects, the UE 115 further: reserves a second
resource in a shared portion of the second COT; and wherein the
continuous transmission operation includes to continuously transmit
for one or more second slots of the second COT before the second
reserved resource based on successfully performing the LBT CAT 4
operation; and transmits a third transmission in the second
reserved resource.
[0172] In a fifteenth aspect, alone or in combination with one or
more of the above aspects, the UE 115 further: reduces a shared
portion of the second COT; and increases the non-shared portion of
the second COT to generate an enlarged non-shared portion of the
second COT, wherein a reserved resource (RR) of the UE is scheduled
in the enlarged non-shared portion of the second COT.
[0173] In a sixteenth aspect, alone or in combination with one or
more of the above aspects, the UE 115 further reserves a particular
subchannel of the second COT, and wherein to perform the continuous
transmission operation includes to transmit a continuous
transmission in the particular subchannel of the second COT.
[0174] In a seventeenth aspect, alone or in combination with one or
more of the above aspects, the reserved particular subchannel is
excluded from other UE resource selection or reservation in the
non-shared portion, the shared portion, or both, of the second COT,
wherein the apparatus prioritizes the reserved particular
subchannel for resource reservation, and wherein the apparatus
prioritizes earlier time slots within the reserved particular
subchannel.
[0175] In an eighteenth aspect, alone or in combination with one or
more of the above aspects, performing the continuous transmission
operation includes to continuously transmit packets before a
reserved resource (RR) in the shared portion of the second COT.
[0176] In a nineteenth aspect, alone or in combination with one or
more of the above aspects, the UE 115 is excluded from resource
selection or reservation in the reserved particular subchannel in
the non-shared portion, the shared portion, or both, of the second
COT.
[0177] In a twentieth aspect, alone or in combination with one or
more of the above aspects, performing the continuous transmission
operation includes leaving a LBT gap for each slot in the reserved
particular subchannel for other apparatuses to clear before
transmitting in other subchannels.
[0178] In a twenty-first aspect, alone or in combination with one
or more of the above aspects, the UE 115 further: determines, prior
to transmitting the second transmission, that a future reserved
resource (RR) of the apparatus is scheduled in a shared portion of
the second COT, which is assigned to the apparatus; and moves the
future RR of the apparatus to the non-shared portion of the second
COT, the future RR corresponding to the second transmission.
[0179] In a twenty-second aspect, alone or in combination with one
or more of the above aspects, the UE 115 further: determines that a
second future RR of the apparatus is scheduled in the shared
portion of the second COT; and moves the second future RR of the
apparatus to the non-shared portion of the second COT.
[0180] In a twenty-third aspect, alone or in combination with one
or more of the above aspects, the second LBT CAT 1 or 2 operation
is performed before the future RR based on determining a second
transmission block (TB) is ready to be transmitted in a second HARQ
process different from a first HARQ process of the first COT, and
the UE 115 further: transmits a third transmission for the second
TB at a first time in a first subchannel of the non-shared portion
of the second COT, wherein the future RR is scheduled at the first
time in a second subchannel of the non-shared portion of the second
COT, wherein the second future RR is scheduled at a second time in
the first subchannel of the non-shared portion of the second COT,
and wherein the third transmission is frequency division
multiplexed with the second transmission of the future RR.
[0181] In a twenty-fourth aspect, alone or in combination with one
or more of the above aspects, the UE 115 further: determines
whether a reserved resource (RR) for the second transmission is
within the second COT or outside of the second COT; and determines
a RSRP threshold for resource selection based on determining
whether the RR is within the second COT or outside of the second
COT.
[0182] In a twenty-fifth aspect, alone or in combination with one
or more of the above aspects, the RR is outside of the second COT,
and determining the RSRP threshold for resource selection includes:
reducing a value of the RSRP threshold by a priority offset value;
or selecting a second RSRP threshold that is less than a first RSRP
threshold for RRs inside of the second COT.
[0183] In a twenty-sixth aspect, alone or in combination with one
or more of the above aspects, the UE 115 further: receives a SCI
transmission from another UE requesting to schedule a reserved
resource (RR) for the other UE in a non-shared portion of a second
COT allocated to the UE, wherein the SCI transmission indicates
offset information and subchannel information for the RR;
determines to block the request; determines to schedule the RR for
the other UE in a shared portion of the second COT; and transmits a
message to the other UE indicating that the RR for the other UE has
been moved to the shared portion of the second COT.
[0184] In a twenty-seventh aspect, alone or in combination with one
or more of the above aspects, the message is a SCI-1, wherein the
SCI-1 indicates a slot offset and subchannel for the RR for the
other UE, and wherein the SCI-1 is associated with a single HARQ
ID.
[0185] In a twenty-eighth aspect, alone or in combination with one
or more of the above aspects, the UE 115 further: transmits a
plurality of SCI-1 transmissions, including the SCI-1, wherein
multiple sets of RRs are associated with multiple HARQ IDs.
[0186] In a twenty-ninth aspect, alone or in combination with one
or more of the above aspects, the UE 115 further: determines that a
second reserved resource (RR) for the UE has blocked a RR for a
second UE in a non-shared portion of the second COT; determines to
schedule the RR for the second UE to a shared portion of the second
COT based on determining that the second RR for the UE has blocked
the RR for the second UE in the non-shared portion of the second
COT; and transmits a sidelink channel information (SCI)
transmission to the second UE to schedule the RR for the second UE,
wherein the second UE uses single step resource selection.
[0187] In a thirtieth aspect, alone or in combination with one or
more of the above aspects, the SCI transmission corresponds to a
SCI-2 transmission, wherein the SCI-2 transmission indicates
information for the relocation of the RR for the second UE, and
wherein the SCI-2 transmission includes source ID information which
indicates a transmitting UE ID for the RR (reservation),
destination ID information which indicates a receiving UE ID for
the RR, HARQ ID information which indicates the RR associated with
specific HARQ ID has been relocated, or a combination thereof.
[0188] Accordingly, a UE and a base station may perform enhanced
resource reservation operations. By performing enhanced resource
reservation operations, throughput and reliability may be increased
and such operations may enable increased spectrum sharing for
sidelink operations with reduced capability (e.g., less advanced)
devices.
[0189] FIG. 12 is a flow diagram illustrating example blocks
executed by a UE configured according to another aspect of the
present disclosure. The example blocks will also be described with
respect to UE 115 as illustrated in FIG. 13.
[0190] At block 1200, a wireless communication device, such as a
UE, operates in a single step resource reservation mode. For
example, the UE 115 is configured to operate in a random resource
reservation or selection mode, as described with reference to FIG.
6.
[0191] At block 1201, the UE 115 determines whether a future
reserved resource (RR) is within a Channel Occupancy Time (COT) of
the UE or outside of the COT. For example, the UE 115 determines
whether an upcoming RR falls within a COT of the UE or outside a
COT of the UE, as described with reference to FIGS. 4-10. To
illustrate, the UE 115 determines if the RR is in a COT allocated
to the UE and/or in shared portion of a COT which belongs to
another UE.
[0192] At block 1202, the UE 115 determines a RSRP threshold for
resource reservation based on determining whether the RR is within
the COT or outside of the COT. For example, the UE 115 determines
to use an alternative RSRP threshold for candidate resource
determination, as described with reference to FIGS. 4, 6, and 9. To
illustrate, the UE 115 may determine to use a higher RSRP threshold
for Out-of-COT RRs, a lower RSRP threshold for in-COT RRs, or both.
Thus, the UE 115 may have different resources available to it than
other UEs might to priority the UE or the other UE.
[0193] The UE 115 may execute additional blocks (or the UE 115 may
be configured further perform additional operations) in other
implementations. For example, the UE 115 may perform one or more
operations or aspects described above or as described with
reference to FIG. 11.
[0194] Accordingly, a UE and a base station may perform enhanced
resource reservation operations. By performing enhanced resource
reservation operations, throughput and reliability may be increased
and such operations may enable increased spectrum sharing for
sidelink operations with reduced capability (e.g., less advanced)
devices.
[0195] Those of skill in the art would understand that information
and signals may be represented using any of a variety of different
technologies and techniques. For example, data, instructions,
commands, information, signals, bits, symbols, and chips that may
be referenced throughout the above description may be represented
by voltages, currents, electromagnetic waves, magnetic fields or
particles, optical fields or particles, or any combination
thereof.
[0196] The functional blocks and modules in FIGS. 11 and 12 may
comprise processors, electronics devices, hardware devices,
electronics components, logical circuits, memories, software codes,
firmware codes, etc., or any combination thereof.
[0197] Those of skill would further appreciate that the various
illustrative logical blocks, modules, circuits, and algorithm steps
described in connection with the disclosure herein may be
implemented as electronic hardware, computer software, or
combinations of both. To clearly illustrate this interchangeability
of hardware and software, various illustrative components, blocks,
modules, circuits, and steps have been described above generally in
terms of their functionality. Whether such functionality is
implemented as hardware or software depends upon the particular
application and design constraints imposed on the overall system.
Skilled artisans may implement the described functionality in
varying ways for each particular application, but such
implementation decisions should not be interpreted as causing a
departure from the scope of the present disclosure. Skilled
artisans will also readily recognize that the order or combination
of components, methods, or interactions that are described herein
are merely examples and that the components, methods, or
interactions of the various aspects of the present disclosure may
be combined or performed in ways other than those illustrated and
described herein.
[0198] The various illustrative logical blocks, modules, and
circuits described in connection with the disclosure herein may be
implemented or performed with a general-purpose processor, a
digital signal processor (DSP), an application specific integrated
circuit (ASIC), a field programmable gate array (FPGA) or other
programmable logic device, discrete gate or transistor logic,
discrete hardware components, or any combination thereof designed
to perform the functions described herein. A general-purpose
processor may be a microprocessor, but in the alternative, the
processor may be any conventional processor, controller,
microcontroller, or state machine. A processor may also be
implemented as a combination of computing devices, e.g., a
combination of a DSP and a microprocessor, a plurality of
microprocessors, one or more microprocessors in conjunction with a
DSP core, or any other such configuration.
[0199] The steps of a method or algorithm described in connection
with the disclosure herein may be embodied directly in hardware, in
a software module executed by a processor, or in a combination of
the two. A software module may reside in RAM memory, flash memory,
ROM memory, EPROM memory, EEPROM memory, registers, hard disk, a
removable disk, a CD-ROM, or any other form of storage medium known
in the art. An exemplary storage medium is coupled to the processor
such that the processor can read information from, and write
information to, the storage medium. In the alternative, the storage
medium may be integral to the processor. The processor and the
storage medium may reside in an ASIC. The ASIC may reside in a user
terminal. In the alternative, the processor and the storage medium
may reside as discrete components in a user terminal.
[0200] In one or more exemplary designs, the functions described
may be implemented in hardware, software, firmware, or any
combination thereof. If implemented in software, the functions may
be stored on or transmitted over as one or more instructions or
code on a computer-readable medium. Computer-readable media
includes both computer storage media and communication media
including any medium that facilitates transfer of a computer
program from one place to another. Computer-readable storage media
may be any available media that can be accessed by a general
purpose or special purpose computer. By way of example, and not
limitation, such computer-readable media can comprise RAM, ROM,
EEPROM, CD-ROM or other optical disk storage, magnetic disk storage
or other magnetic storage devices, or any other medium that can be
used to carry or store desired program code means in the form of
instructions or data structures and that can be accessed by a
general-purpose or special-purpose computer, or a general-purpose
or special-purpose processor. Also, a connection may be properly
termed a computer-readable medium. For example, if the software is
transmitted from a website, server, or other remote source using a
coaxial cable, fiber optic cable, twisted pair, or digital
subscriber line (DSL), then the coaxial cable, fiber optic cable,
twisted pair, or DSL, are included in the definition of medium.
Disk and disc, as used herein, includes compact disc (CD), laser
disc, optical disc, digital versatile disc (DVD), floppy disk and
blu-ray disc where disks usually reproduce data magnetically, while
discs reproduce data optically with lasers. Combinations of the
above should also be included within the scope of computer-readable
media.
[0201] As used herein, including in the claims, the term "and/or,"
when used in a list of two or more items, means that any one of the
listed items can be employed by itself, or any combination of two
or more of the listed items can be employed. For example, if a
composition is described as containing components A, B, and/or C,
the composition can contain A alone; B alone; C alone; A and B in
combination; A and C in combination; B and C in combination; or A,
B, and C in combination. Also, as used herein, including in the
claims, "or" as used in a list of items prefaced by "at least one
of" indicates a disjunctive list such that, for example, a list of
"at least one of A, B, or C" means A or B or C or AB or AC or BC or
ABC (i.e., A and B and C) or any of these in any combination
thereof
[0202] The previous description of the disclosure is provided to
enable any person skilled in the art to make or use the disclosure.
Various modifications to the disclosure will be readily apparent to
those skilled in the art, and the generic principles defined herein
may be applied to other variations without departing from the
spirit or scope of the disclosure. Thus, the disclosure is not
intended to be limited to the examples and designs described herein
but is to be accorded the widest scope consistent with the
principles and novel features disclosed herein.
* * * * *